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Revenues - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Revenues - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative effect of adoption to retained earning	$ 1,211,018	$ 1,311,192	$ 1,035,744	$ 1,020,305
Contract liability, revenue recognized	157,400	122,700
Deferred revenue acquired	22,400	28,000
Retained earnings
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative effect of adoption to retained earning	$ 809,107	$ 891,526	$ 769,575	723,062
Cumulative Effect, Period of Adoption, Adjustment
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative effect of adoption to retained earning				1,599
Cumulative Effect, Period of Adoption, Adjustment \| Retained earnings
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative effect of adoption to retained earning				$ 1,599