Leases - Contractual maturities and future minimum rental payments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Contractual maturities of operating lease liabilities
2019 (remainder)	$ 1,693
2020	31,541
2021	30,392
2022	27,096
2023	22,290
2024 and thereafter	55,080
Total undiscounted lease liability	168,092
Less: present value adjustment	(20,767)
Operating lease liability	$ 147,325
Future minimum rental commitments:
2019		$ 31,088
2020		30,491
2021		29,351
2022		26,068
2023		21,408
2024 and thereafter		54,745
Total future minimum payments		$ 193,151

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

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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