Long-term Debt and Lease Obligations - Equipment Capital Leases (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Equipment Capital Leases
2018	$ 40,129
2019	29
2020	0
2021	0
2022	120,569
Total	160,727
Short-Term and Long-Term Debt
Equipment Capital Leases
2018	38,497
2019	0
2020	0
2021	0
2022	120,569
Total	159,066
Capital Lease Obligations
Equipment Capital Leases
2018	250
2019	29
2020	0
2021	0
2022	0
Total	279
Other Financing
Equipment Capital Leases
2018	1,382
2019	0
2020	0
2021	0
2022	0
Total	$ 1,382

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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