Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements - National Financial Instruments Measured at Fair Value on Recurring Basis (Detail)

v3.8.0.1
Fair Value Measurements - National Financial Instruments Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Thousands
Dec. 31, 2017
Sep. 30, 2017
Dec. 31, 2016
Sep. 30, 2016
Assets        
Long-term investments, at fair value $ 1,390   $ 1,414  
Total 1,390   1,414  
Liabilities        
Liabilities 14,846   5,168  
National Holdings Corporation [Member]        
Assets        
Total   $ 7,102   $ 2,357
Liabilities        
Liabilities   6,059   14,657
Contingently Issuable Warrant [Member]        
Liabilities        
Liabilities     302  
Warrant [Member]        
Liabilities        
Liabilities 87   179  
Warrant [Member] | National Holdings Corporation [Member]        
Assets        
Total   5,665    
Helocyte Convertible Note One [Member]        
Liabilities        
Liabilities 4,700   4,487  
Avenue Convertible Note [Member]        
Liabilities        
Liabilities     200  
Corporate stock Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   116   101
Liabilities        
Liabilities       298
Municipal bonds Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   1,239   2,111
Liabilities        
Liabilities   151    
Restricted stock Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   82   145
Warrants Issuable [Member] | National Holdings Corporation [Member]        
Liabilities        
Liabilities   5,597   14,359
Caelum Convertible Notes [Member]        
Liabilities        
Liabilities 10,059      
Contingent consideration [Member] | National Holdings Corporation [Member]        
Liabilities        
Liabilities   311    
Fair Value, Inputs, Level 1 [Member]        
Assets        
Long-term investments, at fair value 0   0  
Total 0   0  
Liabilities        
Liabilities 0   0  
Fair Value, Inputs, Level 1 [Member] | National Holdings Corporation [Member]        
Assets        
Total   1,355   101
Liabilities        
Liabilities   0   298
Fair Value, Inputs, Level 1 [Member] | Contingently Issuable Warrant [Member]        
Liabilities        
Liabilities     0  
Fair Value, Inputs, Level 1 [Member] | Warrant [Member]        
Liabilities        
Liabilities 0   0  
Fair Value, Inputs, Level 1 [Member] | Warrant [Member] | National Holdings Corporation [Member]        
Assets        
Total   0    
Fair Value, Inputs, Level 1 [Member] | Helocyte Convertible Note One [Member]        
Liabilities        
Liabilities 0   0  
Fair Value, Inputs, Level 1 [Member] | Avenue Convertible Note [Member]        
Liabilities        
Liabilities     0  
Fair Value, Inputs, Level 1 [Member] | Corporate stock Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   116   101
Fair Value, Inputs, Level 1 [Member] | Municipal bonds Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   0   0
Liabilities        
Liabilities   0    
Fair Value, Inputs, Level 1 [Member] | Restricted stock Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   0   0
Fair Value, Inputs, Level 1 [Member] | Corporate stock Liabilities [Member] | National Holdings Corporation [Member]        
Liabilities        
Liabilities       298
Fair Value, Inputs, Level 1 [Member] | Warrants Issuable [Member] | National Holdings Corporation [Member]        
Assets        
Total   0    
Fair Value, Inputs, Level 1 [Member] | Caelum Convertible Notes [Member]        
Liabilities        
Liabilities 0      
Fair Value, Inputs, Level 1 [Member] | Contingent consideration [Member] | National Holdings Corporation [Member]        
Assets        
Total   0    
Fair Value, Inputs, Level 2 [Member]        
Assets        
Long-term investments, at fair value 0   0  
Total 0   0  
Liabilities        
Liabilities 0   0  
Fair Value, Inputs, Level 2 [Member] | National Holdings Corporation [Member]        
Assets        
Total   1,321   2,256
Liabilities        
Liabilities   151   0
Fair Value, Inputs, Level 2 [Member] | Contingently Issuable Warrant [Member]        
Liabilities        
Liabilities     0  
Fair Value, Inputs, Level 2 [Member] | Warrant [Member]        
Liabilities        
Liabilities 0   0  
Fair Value, Inputs, Level 2 [Member] | Warrant [Member] | National Holdings Corporation [Member]        
Assets        
Total   0    
Fair Value, Inputs, Level 2 [Member] | Helocyte Convertible Note One [Member]        
Liabilities        
Liabilities 0   0  
Fair Value, Inputs, Level 2 [Member] | Avenue Convertible Note [Member]        
Liabilities        
Liabilities     0  
Fair Value, Inputs, Level 2 [Member] | Corporate stock Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   0    
Fair Value, Inputs, Level 2 [Member] | Municipal bonds Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   1,239   2,111
Liabilities        
Liabilities   151    
Fair Value, Inputs, Level 2 [Member] | Restricted stock Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   82   145
Fair Value, Inputs, Level 2 [Member] | Corporate stock Liabilities [Member] | National Holdings Corporation [Member]        
Liabilities        
Liabilities       0
Fair Value, Inputs, Level 2 [Member] | Warrants Issuable [Member] | National Holdings Corporation [Member]        
Liabilities        
Liabilities   0    
Fair Value, Inputs, Level 2 [Member] | Caelum Convertible Notes [Member]        
Liabilities        
Liabilities 0      
Fair Value, Inputs, Level 2 [Member] | Contingent consideration [Member] | National Holdings Corporation [Member]        
Liabilities        
Liabilities   0    
Fair Value, Inputs, Level 3 [Member]        
Assets        
Long-term investments, at fair value 1,390   1,414  
Total 1,390   1,414  
Liabilities        
Liabilities 14,846   5,168  
Fair Value, Inputs, Level 3 [Member] | National Holdings Corporation [Member]        
Assets        
Total   5,665   0
Liabilities        
Liabilities   5,908   14,359
Fair Value, Inputs, Level 3 [Member] | Contingently Issuable Warrant [Member]        
Liabilities        
Liabilities     302  
Fair Value, Inputs, Level 3 [Member] | Warrant [Member]        
Liabilities        
Liabilities 87   179  
Fair Value, Inputs, Level 3 [Member] | Warrant [Member] | National Holdings Corporation [Member]        
Assets        
Total   5,665    
Fair Value, Inputs, Level 3 [Member] | Helocyte Convertible Note One [Member]        
Liabilities        
Liabilities 4,700   4,487  
Fair Value, Inputs, Level 3 [Member] | Avenue Convertible Note [Member]        
Liabilities        
Liabilities     $ 200  
Fair Value, Inputs, Level 3 [Member] | Corporate stock Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   0   0
Fair Value, Inputs, Level 3 [Member] | Municipal bonds Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   0   0
Liabilities        
Liabilities   0    
Fair Value, Inputs, Level 3 [Member] | Restricted stock Assets [Member] | National Holdings Corporation [Member]        
Assets        
Total   0   0
Fair Value, Inputs, Level 3 [Member] | Corporate stock Liabilities [Member] | National Holdings Corporation [Member]        
Liabilities        
Liabilities       0
Fair Value, Inputs, Level 3 [Member] | Warrants Issuable [Member] | National Holdings Corporation [Member]        
Liabilities        
Liabilities   5,597   $ 14,359
Fair Value, Inputs, Level 3 [Member] | Caelum Convertible Notes [Member]        
Liabilities        
Liabilities $ 10,059      
Fair Value, Inputs, Level 3 [Member] | Contingent consideration [Member] | National Holdings Corporation [Member]        
Liabilities        
Liabilities   $ 311