Stock Plans and Stock-Based Compensation - Stock Options - Additional Information (Details) - USD ($) $ 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	$ 11,278	$ 8,282	$ 21,588	$ 16,131
Intrinsic value of options exercised			15,400	37,100
Intrinsic value of all outstanding options	59,400	61,700	59,400	61,700
Total unrecognized compensation cost	4,800		4,800
Proceeds from stock option exercises			$ 4,585	$ 13,487
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options vesting period			4 years
Stock options expiration period			10 years
Stock options granted			0	0
Stock-based compensation expense	$ 1,000	$ 1,600	$ 1,900	$ 3,500
Weighted-average amortization period			1 year 4 months 24 days

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

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