Loss And Loss Adjustment Expense Reserves (Schedule Of Present Value Of The Probability-Weighted Future Claim Payments And Recoveries) (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Loss Reserves Claim Liability [Member] \| Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	$ 464,000,000	$ 580,000,000
Lae Reserves [Member] \| Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	42,000,000	61,000,000
Loss And Lae Reserves [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	506,000,000	641,000,000	853,000,000
Loss And Lae Reserves [Member] \| Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	506,000,000	641,000,000
Insurance Loss Recoverable [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Insurance loss recoverable	(533,000,000)	(694,000,000)	(3,648,000,000)
Insurance Loss Recoverable [Member] \| Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Insurance claim loss recoverable	(533,000,000)	(694,000,000)
LAE insurance loss recoverable	0	0
Insurance loss recoverable	(533,000,000)	(694,000,000)
Reinsurance recoverable on unpaid losses	6,000,000	7,000,000
Reinsurance recoverable on unpaid LAE	1,000,000	1,000,000
Reinsurance recoverable on paid losses	0	0
Reinsurance recoverable on paid and unpaid losses	$ 7,000,000	$ 8,000,000

Carrying amount as of the balance sheet date of paid insurance policy claims and LAE expense expected to be recovered.

No definition available.

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- Definition

Carrying amount as of the balance sheet date of paid LAE expenses expected to be recovered.

+ References

No definition available.

+ Details

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- Definition

Reinsurance Recoverable On Unpaid LAE

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of amounts expected to be recovered under the terms of insurance contracts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

+ Details

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- Definition

The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

-Subparagraph (a),(b),(c)

-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

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- Definition

The sum for all reinsurance arrangements of the known and estimated amount recoverable as of the balance sheet date from a given reinsurer for claims paid or incurred by the ceding insurer and associated claims settlement expenses for each reinsurance arrangement (or, the sum of all cases determined individually, probably applying different assumptions to each arrangement).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6485522&loc=d3e21412-158489

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6485522&loc=d3e21409-158489

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.6)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 6

-Article 7

+ Details

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- Definition

Estimated amount after valuation allowance of reinsurance recoverables, due from reinsurers for incurred claims not yet reported, and claims settlement expenses.

+ References

+ Details

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- Definition

Amount after valuation allowance currently billed or billable under reinsurance contracts.

+ References

+ Details

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