Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 4,440	$ 4,802	$ 17,950	$ 15,781
Proceeds from stock options exercised	$ 1,500	$ 3,900	$ 1,619	$ 26,998
Shares issued upon exercise of stock options (in shares)	78,028	242,723	91,589	1,686,408
Total intrinsic value of stock options exercised	$ 800	$ 3,700	$ 900	$ 29,400
Unrecognized compensation cost related to stock options outstanding	6,700		$ 6,700
Recognition period for compensation cost related to awards outstanding			1 year 4 months 24 days
Weighted-average grant date fair value per share of stock options (in dollars per share)			$ 9.05	$ 13.82
Total income tax benefits	(701)	9,561	$ 3,694	$ 7,890
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,400	2,000	6,900	6,800
Total income tax benefits			3,000	12,400
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 3,000	$ 2,800	$ 11,000	$ 8,900
Recognition period for compensation cost related to awards outstanding			1 year 4 months 24 days
Restricted stock units granted (in shares)	45,834	51,546	738,964	459,985
Fair market value of restricted stock units	$ 1,400	$ 1,600	$ 17,900	$ 15,700
Number of unvested restricted stock units (in shares)	1,175,551		1,175,551
Unrecognized compensation cost related to restricted stock units	$ 15,800		$ 15,800

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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