Debt - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Amortization of debt issuance costs			$ 272	$ 1,060
Capital leases	$ 0	$ 241	0	724
Other	101	345	615	667
Total	203	1,370	1,251	3,935
2019 Notes
Debt Instrument [Line Items]
Amortization of debt issuance costs	36	354	273	1,060
Interest on borrowings	66	430	363	1,292
Additional interest on default	$ 0	$ 0	$ 0	$ 192

Additional Interest Expense on Default

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- Definition

Amount of amortization expense attributable to debt issuance costs.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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- Definition

The amount, during the lease term, of each minimum [capital] lease payment allocated to interest expense so as to produce a constant periodic rate of interest on the remaining balance of the capital lease obligation.

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- Definition

Amount of interest expense classified as other.

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