Consolidated Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated provision for uncollectible accounts - customers
Consolidated Valuation and Qualifying Accounts
Beginning Balance	$ 48,937	$ 48,409	$ 60,309
Charged to Income	77,254	73,486	76,953
Charged to Other Accounts	60,307	49,728	15,222
Deductions	136,700	122,686	104,075
Ending Balance	49,798	48,937	48,409
Accumulated provision for uncollectible accounts - other
Consolidated Valuation and Qualifying Accounts
Beginning Balance	990	884	2,731
Charged to Income	12,487	6,461	13,597
Charged to Other Accounts	0	0	11,329
Deductions	11,699	6,355	26,773
Ending Balance	1,778	990	884
Accumulated provision for uncollectible accounts - affiliated companies
Consolidated Valuation and Qualifying Accounts
Beginning Balance	0
Deductions	919,851
Ending Balance	919,851	0
Valuation allowance on various DTAs (3)
Consolidated Valuation and Qualifying Accounts
Beginning Balance	312,135	240,289	146,589
Charged to Income	81,977	71,846	93,700
Charged to Other Accounts	0	0	0
Deductions	0	0	0
Ending Balance	$ 394,112	$ 312,135	$ 240,289

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

+ Details

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

+ References

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to accounts other than cost and expense.

+ References

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- Definition

Amount of decrease in valuation and qualifying accounts and reserves.

+ References

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