Leases - Lease Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Operating Lease Liabilities, Payments Due (Topic 842)
2019 (excluding the six months ended June 30, 2019)	$ 7,637
2020	16,210
2021	16,337
2022	14,838
2023	13,265
Thereafter	60,495
Total undiscounted lease payments	128,782
Adjustment to discount to present value	(23,353)
Total operating lease liabilities	$ 105,429	$ 0
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity (Topic 840)
2019		14,123
2020		15,340
2021		15,215
2022		13,748
2023		12,378
Thereafter		57,185
Total undiscounted lease payments		$ 127,989

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

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