Debt Instruments - Financing of Beneficial Interests in Securitizations (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
Pledged beneficial interests in securitization as collateral	$ 85,000
Long-term debt	716,739
Long-term debt, current portion	606,644	$ 208,096
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Long-term debt	82,700
Long-term debt, current portion	$ 26,400

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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Amount of consolidated variable interest entity's (VIE) assets that can only be used to settle obligations of VIE.

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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.

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