Supplemental Guarantor Information (Supplemental Condensed Consolidated Statement Of Cash Flows) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by/(used in) operating activities	$ (216,997)	$ (125,409)
Net cash used in investing activities	(39,657)	(66,122)
Financing activities
Borrowings under revolving credit facilities	520,000	75,000
Payments on revolving credit facilities	(284,000)	(270,000)
Proceeds from insurance notes payable	11,838
Extinguishments of debt assumed in business combination	(94,231)	(151,919)
Principal payments on notes payable	(2,173)	(4,735)
Proceeds from issuance of senior notes		523,000
Debt issuance costs	(3,521)	(3,731)
Repurchases of common stock upon vesting of restricted stock awards	(5,483)	(4,141)
Net proceeds from mortgage repurchase facilities	9,008	27,465
Net proceeds from issuances of common stock	31,230	35,010
Net cash provided by (used in) financing activities	182,668	225,949
Net increase (decrease)	(73,986)	34,418
Cash and cash equivalents and Restricted cash, Beginning of period	93,713	30,954
Cash and cash equivalents and Restricted cash, End of period	19,727	65,372
Cash and cash equivalents	15,927	58,522	$ 88,832
Restricted Cash	3,800	6,850
Elimination Entries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by/(used in) operating activities	(16,580)
Net cash used in investing activities	280,048	432,867
Financing activities
Payments from (and advances to) parent/subsidiary	(280,048)	(432,867)
Net cash provided by (used in) financing activities	(280,048)	(432,867)
Net increase (decrease)	(16,580)
Cash and cash equivalents and Restricted cash, End of period	(16,580)
Cash and cash equivalents	(16,580)
Century [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by/(used in) operating activities	(71,743)	(8,164)
Net cash used in investing activities	(153,607)	(434,617)
Financing activities
Borrowings under revolving credit facilities	520,000	75,000
Payments on revolving credit facilities	(284,000)	(270,000)
Extinguishments of debt assumed in business combination	(94,231)
Principal payments on notes payable	(9)
Proceeds from issuance of senior notes		523,000
Debt issuance costs	(3,521)	(3,731)
Repurchases of common stock upon vesting of restricted stock awards	(5,483)	(4,141)
Payments from (and advances to) parent/subsidiary	5,130	108,887
Net proceeds from issuances of common stock	31,230	35,010
Net cash provided by (used in) financing activities	169,116	464,025
Net increase (decrease)	(56,234)	21,244
Cash and cash equivalents and Restricted cash, Beginning of period	56,234	14,637
Cash and cash equivalents and Restricted cash, End of period		35,881
Cash and cash equivalents		35,881	56,234
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by/(used in) operating activities	(123,418)	(87,231)
Net cash used in investing activities	(165,939)	(63,905)
Financing activities
Proceeds from insurance notes payable	11,838
Extinguishments of debt assumed in business combination		(151,919)
Principal payments on notes payable	(2,164)	(4,735)
Payments from (and advances to) parent/subsidiary	263,120	320,768
Net cash provided by (used in) financing activities	272,794	164,114
Net increase (decrease)	(16,563)	12,978
Cash and cash equivalents and Restricted cash, Beginning of period	28,044	10,150
Cash and cash equivalents and Restricted cash, End of period	11,481	23,128
Cash and cash equivalents	8,922	16,278	23,399
Restricted Cash	2,559	6,850
Non Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by/(used in) operating activities	(5,256)	(30,014)
Net cash used in investing activities	(159)	(467)
Financing activities
Payments from (and advances to) parent/subsidiary	11,798	3,212
Net proceeds from mortgage repurchase facilities	9,008	27,465
Net cash provided by (used in) financing activities	20,806	30,677
Net increase (decrease)	15,391	196
Cash and cash equivalents and Restricted cash, Beginning of period	9,435	6,167
Cash and cash equivalents and Restricted cash, End of period	24,826	6,363
Cash and cash equivalents	23,585	$ 6,363	$ 9,199
Restricted Cash	$ 1,241