Debt (Details) (USD $)	3 Months Ended	6 Months Ended			3 Months Ended												3 Months Ended
	Mar. 31, 2014	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Jun. 30, 2014 Term loans	Dec. 31, 2013 Term loans	Jun. 30, 2014 Debt due 2015	Dec. 31, 2013 Debt due 2015	Jun. 30, 2014 Debt due 2016	Dec. 31, 2013 Debt due 2016	Jun. 30, 2014 Debt due 2017	Dec. 31, 2013 Debt due 2017	Jun. 30, 2014 Debt due 2019	Dec. 31, 2013 Debt due 2019	Jun. 30, 2014 Debt due 2022	Dec. 31, 2013 Debt due 2022	Mar. 31, 2014 Debt due 2024	Jun. 30, 2014 Debt due 2024	Dec. 31, 2013 Debt due 2024	Jun. 30, 2014 Debt due 2037	Dec. 31, 2013 Debt due 2037	Jun. 30, 2014 Debt due 2043	Dec. 31, 2013 Debt due 2043	Jun. 30, 2014 LIBOR Debt due 2018	Dec. 31, 2013 LIBOR Debt due 2018	Jun. 30, 2014 Prime Rate Debt due 2018	Dec. 31, 2013 Prime Rate Debt due 2018
Debt Instrument [Line Items]
Stated interest rate							5.00%		4.75%		5.75%		6.25%		5.25%			4.625%		5.25%		6.70%		5.60%		4.75%
Debt instrument, term																	10 years
Debt instrument, face amount					$ 130,000,000	$ 230,000,000	$ 274,879,000	$ 274,879,000	$ 370,914,000	$ 370,914,000	$ 385,109,000	$ 500,000,000	$ 300,000,000	$ 300,000,000	$ 110,000,000	$ 110,000,000		$ 500,000,000	$ 0	$ 115,041,000	$ 500,000,000	$ 425,000,000	$ 425,000,000	$ 250,000,000	$ 250,000,000	$ 350,000,000	$ 350,000,000
Other		28,779,000		35,502,000
Total long-term debt		3,239,722,000		3,346,295,000
Current portion		274,879,000		0
Long-term debt		2,964,843,000		3,346,295,000
Extinguishment of debt	500,000,000
Gains (losses) on extinguishment of debt	62,000,000
Net proceeds from issuance of notes		492,525,000	411,613,000														493,000,000
Repayments of Long-term Debt		$ 599,850,000	$ 779,637,000		$ 100,000,000