Basis of Presentation - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended	6 Months Ended
	Apr. 30, 2017	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2016
Basis Of Presentation [Line Items]
Stock repurchase program, expiration date	2018-04
Repurchases of outstanding common stock, shares		1,042,455	1,042,455
Repurchases of outstanding common stock		$ 26,400,000	$ 26,405,000	$ 0
Maximum
Basis Of Presentation [Line Items]
Stock repurchase program, authorized amount	$ 50,000,000
Maximum | Accounting Standard Update (“ASU”) No. 2016-09
Basis Of Presentation [Line Items]
Discrete adjustments to income tax expense recognized			$ 100,000