Annual report pursuant to Section 13 and 15(d)

Fair Value Disclosures (Details 1)

v2.4.0.6
Fair Value Disclosures (Details 1) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2011
6.25% senior notes due 2015 [Member]
Level 2 [Member]
Dec. 31, 2012
7.731% senior subordinated notes due 2017 [Member]
Level 2 [Member]
Dec. 31, 2011
7.731% senior subordinated notes due 2017 [Member]
Level 2 [Member]
Dec. 31, 2012
7.15% senior notes due 2020 [Member]
Level 2 [Member]
Dec. 31, 2011
7.15% senior notes due 2020 [Member]
Level 2 [Member]
Apr. 30, 2012
7.00% senior notes due 2022 [Member]
Dec. 31, 2012
7.00% senior notes due 2022 [Member]
Level 2 [Member]
Dec. 31, 2012
1.875% convertible senior notes due 2032 [Member]
Dec. 31, 2012
1.875% convertible senior notes due 2032 [Member]
Level 2 [Member]
Debt Instrument [Line Items]                  
Aggregate Principal $ 285,000 $ 99,825 $ 125,875 $ 200,000 $ 200,000 $ 300,000 $ 300,000 $ 126,500 $ 126,500
Fair value of fixed-rate debt                  
Estimated Fair Value $ 278,588 $ 102,950 $ 110,770 $ 220,760 $ 190,000   $ 328,500   $ 127,449