Commitments and Contingencies Operating Lease Obligations (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Contractual Commitments, Commitment [Line Items]
Lease cost	$ 6,074	$ 5,687	$ 17,677	$ 17,044
Variable lease cost	920	829	2,690	2,431
Sublease income	(132)	(190)	(448)	(623)
Total lease costs	6,924	6,378	20,046	19,007
Facility Leases
Contractual Commitments, Commitment [Line Items]
Short-term lease cost	$ 62	$ 52	$ 127	$ 155

Contractual Commitments, Commitment [Line Items]

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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- Definition

Amount of sublease income excluding finance and operating lease expense.

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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