Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Mar. 18, 2013	May 23, 2011
Impaired Long Lived Assets Held And Used [Line Items]
Impairment of long-lived assets	$ 0		$ 0
Fair value of available for sale securities	1,300,000		$ 1,900,000
Change in fair value of available for sale securities	$ (571,000)	$ (2,037,000)
Convertible Notes | 1.50% Senior Subordinated Notes Due March 15, 2018
Impaired Long Lived Assets Held And Used [Line Items]
Debt instrument, interest rate, stated percentage	1.50%	1.50%	1.50%	1.50%	2.50%
Senior Secured Term Loan
Impaired Long Lived Assets Held And Used [Line Items]
Fair value, probability factor	100.00%
Senior Secured Term Loan | Accounts Payable And Accrued Liabilities
Impaired Long Lived Assets Held And Used [Line Items]
Prepayment premium	$ 15,700,000