Guarantor Subsidiaries Financial Information Additional Information (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Senior Notes Due April 2017 at 8.00%
Condensed Financial Statements, Captions [Line Items]
Debt Instrument, Face Amount	$ 1,500,000
Interest rate stated percentage	8.00%
Senior notes due April 2020 at 8.25%
Condensed Financial Statements, Captions [Line Items]
Debt Instrument, Face Amount	1,250,000
Interest rate stated percentage	8.25%
Senior notes due March 2021 at 6.375%
Condensed Financial Statements, Captions [Line Items]
Debt Instrument, Face Amount	$ 250,000
Interest rate stated percentage	6.375%