Savings Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Employees eligible compensation deferral for 401(k) Plan	60.00%
401(k) Plan, employer matching percentage for the first 3% of participants' contribution	100.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	3.00%
401(k) Plan, employer matching percentage for the second 2% of participants' contribution	50.00%
Employer 401K, Employee Contribution matched 50 percent by Employer	2.00%
Employer 401 K Matching Contribution To Employee Maximum	4.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 1.5	$ 1.3	$ 1.3