XML 44 R34.htm IDEA: XBRL DOCUMENT v3.5.0.2
Debt (Summary of Senior Notes) (Details) - USD ($)
Sep. 30, 2016
Jul. 01, 2016
Feb. 29, 2016
Dec. 31, 2015
Debt Instrument [Line Items]        
Net premiums, discounts, and issuance costs $ (12,934,000)     $ (12,163,000)
Senior notes 3,110,066,000     1,576,082,000
Estimated fair value $ 3,270,878,000     1,643,651,000
Other Assets | Accounting Standards Update 2015-03        
Debt Instrument [Line Items]        
Net premiums, discounts, and issuance costs       $ (10,300,000)
6.500% unsecured senior notes due May 2016 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate 6.50%     6.50%
Face amount $ 0     $ 465,245,000
7.625% unsecured senior notes due October 2017 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate 7.625%     7.625%
Face amount $ 123,000,000     $ 123,000,000
4.250% unsecured senior notes due March 2021 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate 4.25% 4.25% 4.25% 4.25%
Face amount $ 700,000,000 $ 400,000,000 $ 300,000,000 $ 0
5.500% unsecured senior notes due March 2026 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate 5.50%     5.50%
Face amount $ 700,000,000     $ 0
5.000% unsecured senior notes due January 2027 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate 5.00%     5.00%
Face amount $ 600,000,000     $ 0
7.875% unsecured senior notes due June 2032 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate 7.875%     7.875%
Face amount $ 300,000,000     $ 300,000,000
6.375% unsecured senior notes due May 2033 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate 6.375%     6.375%
Face amount $ 400,000,000     $ 400,000,000
6.000% unsecured senior notes due February 2035 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate 6.00%     6.00%
Face amount $ 300,000,000     $ 300,000,000