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Loss And Loss Adjustment Expense Reserves (RMBS Recoveries) (Narrative) (Detail) (USD $) In Millions, unless otherwise specified | 9 Months Ended | 12 Months Ended |  |  |  | 9 Months Ended
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Sep. 30, 2013 | Dec. 31, 2012 | Aug. 31, 2013 Rmbs And Heloc And Ces [Member] | May 23, 2013 Rmbs And Heloc And Ces [Member] | Sep. 30, 2013 Second-Lien RMBS Ineligible Mortgage Loans [Member] | Sep. 30, 2013 Second-Lien RMBS Ineligible Mortgage Loans [Member] Minimum [Member] | Sep. 30, 2013 Second-Lien RMBS Ineligible Mortgage Loans [Member] Maximum [Member]
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |  |  |
Federal statutory rate | 35.00% | 35.00% |  |  |  |  |
Estimated insurance recoveries, after income taxes | $ 737 | $ 2,300 |  |  |  |  |
Percentage of recognized estimated recoveries in relationship to consolidated total shareholder's equity | 23.00% | 73.00% |  |  |  |  |
Current risk-free rate associated with underlying transaction, range, minimum |  |  |  |  | 1.40% |  |
Current risk-free rate associated with underlying transaction, range, maximum |  |  |  |  | 2.70% |  |
Remaining weighted average contract period (in years) | 9 years 9 months 18 days | 8 years 8 months 12 days |  |  |  | 5 years 0 months 0 days | 10 years 4 months 24 days
ResCap settlement amount per term sheet |  |  |  | 796 |  |  |
ResCap recovery per disclosure statement |  |  | $ 828 |  |  |  |

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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319 + Details
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