Debt (Tables)

12 Months Ended

Dec. 31, 2014

Debt Disclosure [Abstract]

Schedule of Long-term Debt Instruments [Text Block]

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

	2014		2013
Asset securitization program	$	275,000	$	420,000
3.375% notes, due 2015	252,275		255,004
6.875% senior debentures, due 2018	199,288		199,078
3.00% notes, due 2018	298,989		298,691
6.00% notes, due 2020	299,953		299,945
5.125% notes, due 2021	249,514		249,435
4.50% notes, due 2023	297,964		297,767
7.50% senior debentures, due 2027	198,310		198,170
Interest rate swaps designated as fair value hedges	378		—
Other obligations with various interest rates and due dates	3,782		8,042
	$	2,075,453	$	2,226,132

Schedule of Fair Value of Debt [Text Block]

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

	2014		2013
3.375% notes, due 2015	$	255,000	$	260,000
6.875% senior debentures, due 2018	232,000		228,000
3.00% notes, due 2018	309,000		300,000
6.00% notes, due 2020	339,000		330,000
5.125% notes, due 2021	277,500		260,000
4.50% notes, due 2023	321,000		291,000
7.50% senior debentures, due 2027	254,000		232,000