XML 31 R50.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Losses and Loss Expense Reserve - Summary of Loss Reserve Roll-Forward, Net of Subrogation Recoverable and Reinsurance (Detail) (USD $) In Thousands, unless otherwise specified | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2012 | Dec. 31, 2011
Beginning balance of net loss reserves, net of subrogation recoverable and reinsurance | $ 6,230,780 | $ 4,424,450
Current year: |  |
Establishment of new loss reserves, gross of subrogation and net of reinsurance | 239,294 | 503,697
Claim payments, net of subrogation and reinsurance | (11,508) | (2,442)
Establishment of subrogation recoveries, net of reinsurance |  | (9,761)
Total current year | 227,786 | 491,494
Prior year: |  |
Change in previously established loss reserves, gross of subrogation and net of reinsurance | 487,037 | 1,683,831
Claim payments, net of subrogation and reinsurance | (607,593) | (179,440)
Change in previously established subrogation recoveries, net of reinsurance | 15,861 | (324,151)
Total prior year | (104,695) | 1,180,240
Changes in loss reserves | 123,091 | 1,671,734
Net deconsolidation of certain VIEs |  | 134,596
Ending loss reserves, net of subrogation recoverable and reinsurance | $ 6,353,871 | $ 6,230,780

X
- Definition Change in liability for unpaid claims and claim adjustment expense for deconsolidation of certain variable interest entity(ies). + References No definition available. + Details
Name: | abk_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInDeconsolidation
Namespace Prefix: | abk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Liability for unpaid claims and claims adjustment expense. Changes in subrogation recoveries established in prior years, net of reinsurance. + References No definition available. + Details
Name: | abk_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInEstablishedOfSubrogationRecoveriesPriorYear
Namespace Prefix: | abk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Liability for unpaid claims and claims adjustment expense change in loss reserves current year. + References No definition available. + Details
Name: | abk_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInLossReservesCurrentYear
Namespace Prefix: | abk_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Liability for unpaid claims and claims adjustment expense change in loss reserves prior year. + References No definition available. + Details
Name: | abk_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInLossReservesPriorYear
Namespace Prefix: | abk_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Changes in liability for unpaid claims and claims adjustment expense for loss reserves established in prior years, gross of subrogation and net of reinsurance. + References No definition available. + Details
Name: | abk_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInPreviouslyEstablishedLossReservesPriorYear
Namespace Prefix: | abk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | abk_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangesInCurrentYearAbstract
Namespace Prefix: | abk_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | abk_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangesInPriorYearAbstract
Namespace Prefix: | abk_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Liability for unpaid claims and claims adjustment expense establishment of new loss reserves current year, gross of subrogation and net of reinsurance. + References No definition available. + Details
Name: | abk_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseEstablishmentOfNewLossReservesCurrentYear
Namespace Prefix: | abk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Liability for unpaid claims and claims adjustment expense establishment of subrogation recoveries current year, net of reinsurance. + References No definition available. + Details
Name: | abk_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseEstablishmentOfSubrogationRecoveriesCurrentYear
Namespace Prefix: | abk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of increase (decrease) in reserve for incurred claims and claim adjustment expenses attributable to insured events of prior fiscal years. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-5 -Paragraph 11 -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section W + Details
Name: | us-gaap_CausesOfIncreaseDecreaseInLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of payments made in the reporting period to settle claims incurred in the current period and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Financial Reporting Release (FRR) -Number 403 -Paragraph 04 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-5 -Paragraph 11 -Subparagraph c -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. + Details
Name: | us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of payments made in the reporting period to settle claims incurred in prior periods and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Financial Reporting Release (FRR) -Number 403 -Paragraph 04 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-5 -Paragraph 11 -Subparagraph c -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. + Details
Name: | us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 01-5 -Paragraph 10 -Subparagraph a -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-5 -Paragraph 11 -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. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 17, 18, 19, 20 -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. Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Financial Reporting Release (FRR) -Number 403 -Paragraph 04 -Subparagraph b Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph a -Article 7 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 113 -Paragraph 21, 22, 23, 24, 25 -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. + Details
Name: | us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant