Condensed Consolidating Information (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Consolidating Statements of Cash Flows
Net cash provided by (used in) operating activities	$ 617,572	$ 312,175	$ 445,694
Net cash used in investing activities	(1,747,267)	(152,845)	(191,601)
Net cash provided by (used in) financing activities	1,095,902	(140,091)	(268,937)
Increase (decrease) in cash and equivalents	(33,793)	19,239	(14,844)
Cash and equivalents at beginning of year	395,156	375,917	390,761
Cash and equivalents at end of year	361,363	395,156	375,917
Reportable legal entity \| Parent
Condensed Consolidating Statements of Cash Flows
Net cash provided by (used in) operating activities	400,204	190,616	306,613
Net cash used in investing activities	(1,690,363)	(170,561)	(104,242)
Net cash provided by (used in) financing activities	1,234,606	(21,896)	(180,737)
Increase (decrease) in cash and equivalents	(55,553)	(1,841)	21,634
Cash and equivalents at beginning of year	320,866	322,707	301,073
Cash and equivalents at end of year	265,313	320,866	322,707
Reportable legal entity \| Guarantors
Condensed Consolidating Statements of Cash Flows
Net cash provided by (used in) operating activities	279,080	190,885	209,579
Net cash used in investing activities	(8,883)	(41,415)	(107,274)
Net cash provided by (used in) financing activities	(249,655)	(129,997)	(119,329)
Increase (decrease) in cash and equivalents	20,542	19,473	(17,024)
Cash and equivalents at beginning of year	61,148	41,675	58,699
Cash and equivalents at end of year	81,690	61,148	41,675
Reportable legal entity \| Combined Non-Guarantors
Condensed Consolidating Statements of Cash Flows
Net cash provided by (used in) operating activities	(38,666)	(80,525)	(76,363)
Net cash used in investing activities	(23,206)	(23,086)	(95,314)
Net cash provided by (used in) financing activities	63,090	105,218	152,223
Increase (decrease) in cash and equivalents	1,218	1,607	(19,454)
Cash and equivalents at beginning of year	13,142	11,535	30,989
Cash and equivalents at end of year	14,360	13,142	11,535
Consolidating Adjustments
Condensed Consolidating Statements of Cash Flows
Net cash provided by (used in) operating activities	(23,046)	11,199	5,865
Net cash used in investing activities	(24,815)	82,217	115,229
Net cash provided by (used in) financing activities	$ 47,861	$ (93,416)	$ (121,094)

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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