Debt and Credit Agreements (Details) (USD $)			0 Months Ended		1 Months Ended	3 Months Ended					12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Sep. 15, 2013 Senior Notes [Member] 5.125% notes due September 15, 2013	Dec. 31, 2013 U.S. commercial paper program	Mar. 31, 2012 Credit Agreement bank	Dec. 31, 2013 Credit Agreement		Sep. 30, 2013 Credit Agreement	Dec. 31, 2013 Senior Notes [Member] 5.125% notes due September 15, 2013	Dec. 31, 2012 Senior Notes [Member] 5.125% notes due September 15, 2013	Dec. 31, 2013 Senior Notes [Member] 5.75% notes due May 15, 2018	Dec. 31, 2012 Senior Notes [Member] 5.75% notes due May 15, 2018
Line of Credit Facility [Line Items]
Debt Instrument, Redemption Price, Percentage											5.75%
Debt Issuance Cost						$ 300,000		$ 400,000
Facility Limit					525,000,000	525,000,000	[1]
Stated interest rate			5.125%							5.125%	5.75%	5.75%
Outstanding Balance				35,000,000		35,000,000	[1]
Other Borrowings		89,500,000
Extinguishment of Debt, Amount			150,000,000
Available Credit						490,000,000	[1]
Number of lenders providing credit facility (in banks)					14
Contingent increase to maximum borrowing capacity					550,000,000
Variable basis of interest rates					LIBOR
Short-term borrowings	$ 7,489,000	$ 8,560,000
Weighted average interest rate	10.80%	4.90%

[1] {F|ahBzfndlYmZpbGluZ3MtaHJkcmoLEgZYTUxEb2MiXlhCUkxEb2NHZW5JbmZvOmYwMzE0Y2Q0ZmNiYjQxM2M4NDcyNjBkY2I3M2ExMjZjfFRleHRTZWxlY3Rpb246NDlBNkE4OTk4MDY4NUQ1MUE2NzRDNTBDQTI3MEYyQjcM}