Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Employee Stock Purchase Programs (Detail)

v3.8.0.1
Stockholders' Equity - Employee Stock Purchase Programs (Detail) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense $ 14,005 $ 12,128 $ 14,291
National [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 602 42 0
Avenue [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 604 28 51
Caelum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 595 0 0
Cellvation [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 31 7 0
Checkpoint [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 3,118 3,867 3,252
Helocyte [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 128 250 0
JMC [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 224 515 597
Mustang [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 2,013 0 0
Tamid [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 1 0 0
Employee Awards [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 6,606 7,386 8,130
Executive Awards [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 0 0 2,228
Non-Employee Awards [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense $ 83 $ 33 $ 33