Debt Obligations (5.25% Senior Unsecured Notes) (Narrative) (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	9 Months Ended
Dec. 31, 2010	Sep. 30, 2011
Debt Instrument [Line Items]
Aggregate principal amount purchased plus accrued and unpaid interest		101.00%
Senior Unsecured Bridge Facility [Member]
Debt Instrument [Line Items]
Bridge Facility	$ 400
Debt instrument, interest rate, effective percentage	1.76%
Other borrowings	370
5.25% Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes issued	370
Debt instrument, interest rate, stated percentage		5.25%
Proceeds from unsecured notes payable		367
Cash on hand from unsecured notes payable		3
Debt instrument, principal outstanding		367.0
Maximum interest rate on debt instrument		7.25%
Debt issuance costs		$ 3

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Cash on hand used to repay bridge facility.

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Maximum Interest Rate on Debt Instrument

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Short-Term financing which is expected to be paid back relatively quickly, such as by a subsequent longer-term loan. Also called swing loan or bridge financing.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Interest rate stated in the contractual debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For an unclassified balance sheet, the amount as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain. Such amount is before the consideration of accumulated amortization.

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The fair value of notes issued in noncash investing and financing activities.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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The cash inflow from borrowings supported by a written promise to pay an obligation that is uncollateralized (where debt is not backed by the pledge of collateral).

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