Leases - Operating Lease Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Topic 842
Remainder of 2019	$ 4,901
2020	9,250
2021	8,109
2022	7,628
2023	7,339
Thereafter	65,589
Total undiscounted cash flows	102,816
Discount on cash flows	25,367
Total operating lease liabilities	$ 77,449
Topic 840
2019		$ 9,389
2020		8,199
2021		6,339
2022		4,929
2023		3,711
Thereafter		12,592
Total		$ 45,159

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

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