Debt (Tables)

12 Months Ended

Dec. 31, 2011

Debt Disclosure [Abstract]

Schedule of Long-term Debt Instruments [Text Block]

Long-term debt consists of the following at December 31:

	2011		2010
Revolving credit facility	$	74,000	$	—
Asset securitization program	280,000		—
Bank term loan, due 2012	—		200,000
6.875% senior notes, due 2013	341,937		349,833
3.375% notes, due 2015	260,461		249,155
6.875% senior debentures, due 2018	198,660		198,450
6.00% notes, due 2020	299,927		299,918
5.125% notes, due 2021	249,278		249,199
7.5% senior debentures, due 2027	197,890		197,750
Interest rate swaps designated as fair value hedges	—		14,082
Other obligations with various interest rates and due dates	25,670		2,816
	$	1,927,823	$	1,761,203

Schedule of Fair Value of Debt [Text Block]

The estimated fair market value at December 31, using quoted market prices, is as follows:

	2011		2010
6.875% senior notes, due 2013	$	352,000	$	385,000
3.375% notes, due 2015	250,000		243,000
6.875% senior debentures, due 2018	216,000		218,000
6.00% notes, due 2020	315,000		306,000
5.125% notes, due 2021	247,500		238,000
7.5% senior debentures, due 2027	244,000		204,000