Leases - Maturities of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Remaining nine months of 2019	$ 4,101
2020	5,200
2021	4,724
2022	3,948
2023	3,424
2024	788
Total future minimum lease payments	22,185
Less imputed interest	(2,121)
Total lease liabilities	$ 20,064
2019		$ 5,222
2020		5,251
2021		4,775
2022		3,999
2023		3,421
Thereafter		788
Total		$ 23,456

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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, due after fifth fiscal year following latest fiscal year.

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

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