Leases - Payments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases
2020	$ 8,825
2021	9,067
2022	9,319
2023	7,797
2024	2,400
2025 and thereafter	4,730
Total	42,138
Less: imputed interest	(10,102)
Operating lease liabilities	32,036
2019		$ 8,588
2020		8,825
2021		9,067
2022		9,319
2023		7,702
2024 and thereafter		7,130
Total future minimum lease payments		50,631
Rent expense	$ 7,800	$ 7,400	$ 7,200

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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