v3.10.0.1

Consolidated Statements Of Cash Flows - Supplemental Disclosures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Supplemental Cash Flow Information [Abstract]
Trade accounts receivable and other accounts receivable	$ 24,169	$ (25,639)	$ (31,107)
Inventory	(3,390)	(47,967)	(3,510)
Energy commodity derivatives contracts, net of derivatives deposits	(7,078)	8,556	(692)
Accounts payable	21,146	8,954	(4,423)
Accrued payroll and benefits	14,015	10,596	(6,074)
Accrued interest payable	(7,399)	5,014	14,347
Accrued taxes other than income	1,750	1,177	(1,421)
Deferred revenue	5,191	15,904	20,264
Accrued product purchases	(20,677)	44,559	20,261
Current and noncurrent environmental liabilities	1,226	(4,766)	(7,398)
Other current and noncurrent assets and liabilities	(6,707)	(693)	(21,762)
Changes in components of operating assets and liabilities	$ 22,246	$ 15,695	$ (21,515)

X

- Definition

The adjustment to exclude the noncash portion of, and include cash payments for environmental costs when calculating operating cash flows under the indirect method. The adjustment can include the increase (decrease) during an accounting period in total estimated obligations recorded for probable future loss attributable to environmental contamination issues.

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