Annual report pursuant to Section 13 and 15(d)

Income Taxes - Reconciliation of Statutory Tax Rates and Effective Tax Rates (Detail)

v3.6.0.2
Income Taxes - Reconciliation of Statutory Tax Rates and Effective Tax Rates (Detail)
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Percentage of pre-tax income:      
U.S. federal statutory income tax rate 35.00% 35.00% 35.00%
State taxes, net of federal benefit 3.00% 5.00% 5.00%
Credits 2.00% 1.00% 6.00%
Non-deductible items (4.00%) 0.00% (1.00%)
Provision to return 2.00% 0.00% 0.00%
Stock based compensation shortfall (2.00%) (1.00%) 0.00%
Other 0.00% 1.00% 0.00%
Change in valuation allowance (33.00%) (44.00%) (45.00%)
Change in subsidiary basis (3.00%) 3.00% 0.00%
Effective income tax rate 0.00% 0.00% 0.00%