Lease Obligations - Maturities of Lease Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Operating Leases
2020	$ 13,193
2021	11,975
2022	11,404
2023	11,389
2024	5,257
Thereafter	5,242
Total lease payments	58,460
Less imputed interest	(11,598)
Total	46,862
Finance Leases
2020	1,254
2021	1,070
2022	0
2023	0
2024	0
Thereafter	0
Total lease payments	2,324
Less imputed interest	(186)
Total	2,138	$ 2,938
Total
2020	14,447
2021	13,045
2022	11,404
2023	11,389
2024	5,257
Thereafter	5,242
Total lease payments	60,784
Less imputed interest	(11,784)
Total	$ 49,000

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-Publisher FASB
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-SubTopic 20
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