Borrowings - Company's Debt Position (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Current portion of long-term borrowings	$ 20,657	$ 40,867
Long-term borrowings gross	229,000	209,000
Unamortized debt discount	(12,562)	(13,851)
Unamortized debt issuance cost	(911)	(1,018)
Long-term borrowings	215,527	194,131
Total borrowings	236,184	234,998
Revolver Credit Facility
Debt Instrument [Line Items]
Current portion of long-term borrowings	20,000	40,000
Long-term borrowings gross	79,000	59,000
Unamortized debt discount	0	0
Unamortized debt issuance cost	0	0
Long-term borrowings	79,000	59,000
Total borrowings	99,000	99,000
Unamortized debt issuance costs	619	748
Structured Payables
Debt Instrument [Line Items]
Current portion of long-term borrowings	657	867
Long-term borrowings gross	0	0
Unamortized debt discount	0	0
Unamortized debt issuance cost	0	0
Long-term borrowings	0	0
Total borrowings	657	867
Notes
Debt Instrument [Line Items]
Current portion of long-term borrowings	0	0
Long-term borrowings gross	150,000	150,000
Unamortized debt discount	(12,562)	(13,851)
Unamortized debt issuance cost	(911)	(1,018)
Long-term borrowings	136,527	135,131
Total borrowings	$ 136,527	$ 135,131

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