Loss Exposure on derivatives

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- Definition

Derivative Instruments, Gain (Loss) Included in Accumulated Other Comprehensive (Loss) Income

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- Definition

Notional Amount Of Derivatives, Terminations

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

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-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph i

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

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-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

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- Definition

A disclosure of an assertion that the amount of cash flow hedge ineffectiveness is immaterial.

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- Definition

The amount recognized in earnings related to the change in fair value during the period of derivative or nonderivative instruments designated as fair value hedging instruments.

+ References

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- Definition

The amount recognized in earnings related to the change in fair value during the period of the hedged item in a fair value hedge.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

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- Definition

The amount of the obligation to return cash collateral under master netting arrangements that have not been offset against net derivative instrument positions.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

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-Subparagraph (b)

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- Definition

The amount of the right to reclaim cash collateral under master netting arrangements that have not been offset against net derivative instrument positions.

+ References

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- Definition

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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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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-Publisher FASB

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-Topic 815

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Assertion that the amount of fair value hedge ineffectiveness is immaterial.

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- Definition

Aggregate notional amount of all derivatives. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

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- Definition

Aggregate notional amount of all derivatives designated as a fair value hedging instrument. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

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-Glossary Notional Amount

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- Definition

Aggregate notional amount of all foreign currency derivatives designated as hedging instruments in cash flow hedges. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

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Aggregate notional amount of all interest rate derivatives designated as hedging instruments in cash flow hedges. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

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Aggregate notional amount of all interest rate derivatives designated as hedging instruments in fair value hedges. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

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Derivative Financial Instruments - Additional Information (Detail) (USD $) In Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2011	Sep. 30, 2010	Jun. 30, 2011	Dec. 31, 2010
Derivative [Line Items]
Current credit exposure on derivatives	$ 23.2	$ 23.2
Cash collateral from counterparties	0	0			39.1
Carrying value of fixed maturity securities posted as collateral to our counterparties	131.6	131.6			158.8
Cash Collateral to counterparties	0	0
Aggregate fair value of all derivative instruments with credit risk-related contingent features in a liability position	154.7	154.7			199.6
Notional amount of forward starting interest rate swaps to hedge anticipated purchase of long-term bonds	385.0	385.0			540.0
Notional amount of foreign currency cash flow hedges	574.7	574.7			617.9
Notional Value	1,498.7	1,498.7		1,538.7	1,681.9
Notional amount of terminated swaps	55.0	230.1
Derivative Instruments Gain Loss Included in Accumulated Other Comprehensive Loss Income		(0.1)
Cash Flow Hedge Ineffectiveness is Immaterial		0	0
Approximate amount of net deferred gains on derivative instruments expected to be amortized during the next twelve months		33.6
Ineffectiveness on Interest Rate Fair Value Hedges is Immaterial		0
Swaps \| Derivative Financial Instruments Receive Variable Pay Fixed [Member]
Derivative [Line Items]
Notional amount of receive variable, pay fixed interest rate swaps to hedge changes in fair value of certain fixed rate securities held	174.0	174.0
Notional Value	174.0	174.0		174.0	174.0
Notional amount of terminated swaps	0	0
Hedged benchmark interest rate, on the related interest rate swaps		8.7	15.9
Swaps \| Derivative Financial Instruments Receive Fixed Pay Variable [Member]
Derivative [Line Items]
Notional Value	735.0	735.0		785.0	890.0
Notional amount of terminated swaps	50.0	155.0
Notional amount of hedging instrument	350.0	350.0
Loss on the hedged fixed maturity securities attributable to the hedged benchmark interest rate		22.0
Derivative Financial Instruments Receive Fixed Pay Variable [Member]
Derivative [Line Items]
Notional Value	385.0	385.0
Forward Starting interest rate swap on anticipation of issuance of LT debt [Member]
Derivative [Line Items]
Notional amount of forward starting interest rate swaps to hedge anticipated purchase of long-term bonds			250.0
Derivative Instruments Gain Loss Included in Accumulated Other Comprehensive Loss Income		18.5
Forward Contracts [Member]
Derivative [Line Items]
Notional Value	15.0	15.0		0	0
Notional amount of terminated swaps	$ 0	$ 31.9