Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Line Items]
Change in tax credit carryforwards	$ 113	$ 1,529	$ (8,357)
Tax benefit	(406)	(2,186)	(25,498)
Valuation allowance	71,815	45,983
Increase (decrease) in valuation allowance due to deferred tax assets	(25,800)	3,600
Research and development tax credits	22,082	9,045
Unrecognized tax benefits, if recognized, would affect the effective tax rate	700	700	$ 300
Talon [Member]
Income Taxes [Line Items]
Increase (decrease) in valuation allowance due to deferred tax assets		$ 17,200
Research Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Tax benefit	400
Federal [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 111,500
Net operating loss carryforwards expiration year	2018
Research and development tax credits	$ 22,900
Research and development tax credits beginning expiration year	2027
State [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 92,700
Research and development tax credits	3,000
Foreign [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 8,900
Net operating loss carryforwards expiration year	2022