Leases - Lease Payments, Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019
Operating Leases, After Adoption of 842:
April 1 to December 31, 2019	$ 4,328
2020	5,659
2021	5,337
2022	5,031
2023	2,429
Thereafter	8
Total lease payment	22,792
Less: Interest	3,606
Present value of lease liabilities	19,186	$ 20,200
Operating Leases, Before Adoption of 842:
2019	5,755
2020	5,659
2021	5,337
2022	5,031
2023	2,429
Thereafter	8
Total future minimum lease payments	$ 24,219

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
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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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-SubTopic 20
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