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Stock-based Compensation - Narrative (Details) - USD ($)		3 Months Ended		9 Months Ended
	May 07, 2014	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 29,700,000		$ 29,700,000
Weighted-average period of recognition of unrecognized stock-based compensation cost				1 year 10 months 9 days
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted				0
Stock-based compensation		0	$ 0	$ 0	$ 0
Unrecognized compensation cost		0		0
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation		$ 6,700,000	$ 6,600,000	$ 18,800,000	$ 15,000,000
Number of shares other than options granted				597,728
Restricted Stock With Total Shareholder Return Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares other than options granted				116,599
Equity Incentive Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	0
Number of shares authorized		4,494,268		4,494,268