Condensed Consolidating Financial Information (Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities
Net cash from operating activities	$ 164,090	$ 118,525
Cash flows from investing activities
Capital expenditures	(89,322)	(25,918)
Net activity with affiliates	0	0
Other investing activities	(11,918)	(500)
Net cash used in investing activities	(101,240)	(26,418)
Cash flows from financing activities
Borrowings under bank credit facility	434,829	179,600
Payments under bank credit facility	(466,802)	(264,403)
Debt issue costs	(53)	(9)
Net activity with affiliates	0	0
Share-based compensation activities, net	(2,921)	(3,589)
Stock Repurchased and Retired During Period, Value	(21,653)	(19,803)
Payments of Ordinary Dividends, Common Stock	(6,705)	(5,632)
Proceeds from (Payments for) Combined Other Financing Activities	(115)	(50)
Net cash provided by (used in) financing activities	(63,420)	(113,886)
Cash and cash equivalents, beginning of period	272,632	205,500	$ 273,202	$ 227,279
Net change in cash, cash equivalents and restricted cash	(570)	(21,779)
Parent
Cash flows from operating activities
Net cash from operating activities	(30,882)	(19,900)
Cash flows from investing activities
Capital expenditures	(63,156)	(13,097)
Net activity with affiliates	0	0
Other investing activities	(4,620)	(500)
Net cash used in investing activities	(67,776)	(13,597)
Cash flows from financing activities
Borrowings under bank credit facility	434,829	179,600
Payments under bank credit facility	(466,802)	(264,403)
Debt issue costs	(53)	(9)
Net activity with affiliates	153,873	146,984
Share-based compensation activities, net	(2,921)	(3,589)
Stock Repurchased and Retired During Period, Value	(21,653)	(19,803)
Payments of Ordinary Dividends, Common Stock	6,705	5,632
Proceeds from (Payments for) Combined Other Financing Activities	0	0
Net cash provided by (used in) financing activities	90,568	33,148
Cash and cash equivalents, beginning of period	607	(2)	8,697	347
Net change in cash, cash equivalents and restricted cash	(8,090)	(349)
Guarantor Subsidiaries [Member]
Cash flows from operating activities
Net cash from operating activities	193,653	144,168
Cash flows from investing activities
Capital expenditures	(25,455)	(12,692)
Net activity with affiliates	(153,088)	(154,344)
Other investing activities	(7,298)	0
Net cash used in investing activities	(185,841)	(167,036)
Cash flows from financing activities
Borrowings under bank credit facility	0	0
Payments under bank credit facility	0	0
Debt issue costs	0	0
Net activity with affiliates	0	0
Share-based compensation activities, net	0	0
Stock Repurchased and Retired During Period, Value	0	0
Payments of Ordinary Dividends, Common Stock	0	0
Proceeds from (Payments for) Combined Other Financing Activities	(115)	(50)
Net cash provided by (used in) financing activities	(115)	(50)
Cash and cash equivalents, beginning of period	247,600	191,045	239,903	213,963
Net change in cash, cash equivalents and restricted cash	7,697	(22,918)
Subsidiary, BAC [Member]
Cash flows from operating activities
Net cash from operating activities	0	0
Cash flows from investing activities
Capital expenditures	0	0
Net activity with affiliates	0	0
Other investing activities	0	0
Net cash used in investing activities	0	0
Cash flows from financing activities
Borrowings under bank credit facility	0	0
Payments under bank credit facility	0	0
Debt issue costs	0	0
Net activity with affiliates	0	0
Share-based compensation activities, net	0	0
Stock Repurchased and Retired During Period, Value	0	0
Payments of Ordinary Dividends, Common Stock	0	0
Proceeds from (Payments for) Combined Other Financing Activities	0	0
Net cash provided by (used in) financing activities	0	0
Cash and cash equivalents, beginning of period	0	0	0	0
Net change in cash, cash equivalents and restricted cash	0	0
Non-Guarantor Subsidiaries (100% Owned)
Cash flows from operating activities
Net cash from operating activities	1,490	(5,115)
Cash flows from investing activities
Capital expenditures	(711)	(129)
Net activity with affiliates	0	0
Other investing activities	0	0
Net cash used in investing activities	(711)	(129)
Cash flows from financing activities
Borrowings under bank credit facility	0	0
Payments under bank credit facility	0	0
Debt issue costs	0	0
Net activity with affiliates	(956)	6,732
Share-based compensation activities, net	0	0
Stock Repurchased and Retired During Period, Value	0	0
Payments of Ordinary Dividends, Common Stock	0	0
Proceeds from (Payments for) Combined Other Financing Activities	0	0
Net cash provided by (used in) financing activities	(956)	6,732
Cash and cash equivalents, beginning of period	24,425	14,457	24,602	12,969
Net change in cash, cash equivalents and restricted cash	(177)	1,488
Non-Guarantor Subsidiaries (Not 100% Owned)
Cash flows from operating activities
Net cash from operating activities	0	0
Cash flows from investing activities
Capital expenditures	0	0
Net activity with affiliates	0	0
Other investing activities	0	0
Net cash used in investing activities	0	0
Cash flows from financing activities
Borrowings under bank credit facility	0	0
Payments under bank credit facility	0	0
Debt issue costs	0	0
Net activity with affiliates	0	0
Share-based compensation activities, net	0	0
Stock Repurchased and Retired During Period, Value	0	0
Payments of Ordinary Dividends, Common Stock	0	0
Proceeds from (Payments for) Combined Other Financing Activities	0	0
Net cash provided by (used in) financing activities	0	0
Cash and cash equivalents, beginning of period	0	0	0	0
Net change in cash, cash equivalents and restricted cash	0	0
Eliminations
Cash flows from operating activities
Net cash from operating activities	(171)	(628)
Cash flows from investing activities
Capital expenditures	0	0
Net activity with affiliates	153,088	154,344
Other investing activities	0	0
Net cash used in investing activities	153,088	154,344
Cash flows from financing activities
Borrowings under bank credit facility	0	0
Payments under bank credit facility	0	0
Debt issue costs	0	0
Net activity with affiliates	(152,917)	(153,716)
Share-based compensation activities, net	0	0
Stock Repurchased and Retired During Period, Value	0	0
Payments of Ordinary Dividends, Common Stock	0	0
Proceeds from (Payments for) Combined Other Financing Activities	0	0
Net cash provided by (used in) financing activities	(152,917)	(153,716)
Cash and cash equivalents, beginning of period	0	0	$ 0	$ 0
Net change in cash, cash equivalents and restricted cash	$ 0	$ 0

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Share-based compensation activities, net

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