Debt Short term Debt and Credit Facilities (Details) (USD $)
|
12 Months Ended | ||||
---|---|---|---|---|---|
Dec. 31, 2010
|
Dec. 31, 2010
Credit Facility [Member]
|
Dec. 31, 2010
Short-term Financing Commitments [Member]
|
Dec. 31, 2010
Other Debt [Member]
|
Dec. 31, 2009
Other Debt [Member]
|
|
Debt Issuance [Line Items] | |||||
Line of Credit Facility, Maximum Borrowing Capacity | $ 1,000,000,000 | ||||
Line of Credit Facility, Expiration Date | In August 2012 | ||||
Line of Credit Facility, Interest Rate Description | The agreement calls for interest at either a LIBOR-based rate or a rate based on the prime lending rate of the agent bank, at the company’s option. The rate at December 31, 2010, was between 0.44% and 0.65% (depending on duration) under the more favorable of the two rates. | ||||
Letters Of Credit, Outstanding Amount | 96,400,000 | 48,300,000 | |||
Debt Instrument, Unused Borrowing Capacity, Amount | 951,700,000 | ||||
Short-term Obligations [Abstract] | |||||
Short Term Borrowings | 3,700,000 | 1,900,000 | |||
Short-term Debt, Weighted Average Interest Rate | 10.63% | 11.42% | |||
Line of Credit Facility, Remaining Borrowing Capacity | 69,600,000 | ||||
Short-term Financing Arrangement, Unused Borrowing Capacity Amount | $ 1,500,000,000 | ||||
Debt Instrument, Interest Rate at Period End | 1.75% |