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Financial Guarantee Insurance Contracts - Summary of Information Related to Policies Currently Included in Ambac's Loss Reserves or Subrogation Recoverable (Detail) - Successor [Member] $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2016 USD ($) Policies | Dec. 31, 2015 USD ($) Policies
Schedule of Insured Financial Obligations with Credit Deterioration [Line Items] |  |
Number of policies | Policies | 308 | 293
Remaining weighted-average contract period (in years) | 16 years | 15 years
Gross insured contractual payments outstanding: |  |
Principal | $ 15,599,434 | $ 15,976,009
Interest | 11,883,312 | 11,867,941
Total | 27,482,746 | 27,843,950
Gross undiscounted claim liability | 7,764,322 | 8,192,193
Discount, gross claim liability | 1,026,497 | 1,333,663
Gross claim liability before all subrogation and before reinsurance | 6,737,825 | 6,858,530
Less: |  |
Gross RMBS subrogation | (1,861,904) | (2,841,291)
Discount, RMBS subrogation | 6,831 | 11,716
Discounted RMBS subrogation, before reinsurance | (1,855,073) | (2,829,575)
Less: |  |
Gross other subrogation | (1,409,009) | (1,388,070)
Discount, other subrogation | 268,016 | 334,251
Discounted other subrogation, before reinsurance | (1,140,993) | (1,053,819)
Gross claim liability, net of all subrogation and discounts, before reinsurance | 3,741,759 | 2,975,136
Less: Unearned premium reserves | (167,941) | (189,587)
Plus: Loss adjustment expenses reserves | 69,258 | 73,264
Claim liability reported on Balance Sheet, before reinsurance | 3,643,076 | 2,858,813
Reinsurance recoverable reported on Balance Sheet | $ 27,316 | $ 43,999
I/SL [Member] |  |
Schedule of Insured Financial Obligations with Credit Deterioration [Line Items] |  |
Number of policies | Policies | 40 | 33
Remaining weighted-average contract period (in years) | 10 years | 9 years
Gross insured contractual payments outstanding: |  |
Principal | $ 2,217,143 | $ 1,830,549
Interest | 962,608 | 724,940
Total | 3,179,751 | 2,555,489
Gross undiscounted claim liability | 7,717 | 6,188
Discount, gross claim liability | 534 | 515
Gross claim liability before all subrogation and before reinsurance | 7,183 | 5,673
Less: |  |
Gross RMBS subrogation | 0 | 0
Discount, RMBS subrogation | 0 | 0
Discounted RMBS subrogation, before reinsurance | 0 | 0
Less: |  |
Gross other subrogation | 0 | 0
Discount, other subrogation | 0 | 0
Discounted other subrogation, before reinsurance | 0 | 0
Gross claim liability, net of all subrogation and discounts, before reinsurance | 7,183 | 5,673
Less: Unearned premium reserves | (4,411) | (3,360)
Plus: Loss adjustment expenses reserves | 1,907 | 0
Claim liability reported on Balance Sheet, before reinsurance | 4,679 | 2,313
Reinsurance recoverable reported on Balance Sheet | $ 722 | $ 642
IA [Member] |  |
Schedule of Insured Financial Obligations with Credit Deterioration [Line Items] |  |
Number of policies | Policies | 14 | 14
Remaining weighted-average contract period (in years) | 17 years | 17 years
Gross insured contractual payments outstanding: |  |
Principal | $ 262,318 | $ 263,288
Interest | 107,335 | 107,624
Total | 369,653 | 370,912
Gross undiscounted claim liability | 5,630 | 5,632
Discount, gross claim liability | 502 | 652
Gross claim liability before all subrogation and before reinsurance | 5,128 | 4,980
Less: |  |
Gross RMBS subrogation | 0 | 0
Discount, RMBS subrogation | 0 | 0
Discounted RMBS subrogation, before reinsurance | 0 | 0
Less: |  |
Gross other subrogation | 0 | 0
Discount, other subrogation | 0 | 0
Discounted other subrogation, before reinsurance | 0 | 0
Gross claim liability, net of all subrogation and discounts, before reinsurance | 5,128 | 4,980
Less: Unearned premium reserves | (1,767) | (1,796)
Plus: Loss adjustment expenses reserves | 64 | 66
Claim liability reported on Balance Sheet, before reinsurance | 3,425 | 3,250
Reinsurance recoverable reported on Balance Sheet | $ 920 | $ 880
II [Member] |  |
Schedule of Insured Financial Obligations with Credit Deterioration [Line Items] |  |
Number of policies | Policies | 26 | 23
Remaining weighted-average contract period (in years) | 26 years | 26 years
Gross insured contractual payments outstanding: |  |
Principal | $ 1,962,283 | $ 1,912,237
Interest | 6,835,208 | 6,834,538
Total | 8,797,491 | 8,746,775
Gross undiscounted claim liability | 165,930 | 173,930
Discount, gross claim liability | 83,763 | 96,218
Gross claim liability before all subrogation and before reinsurance | 82,167 | 77,712
Less: |  |
Gross RMBS subrogation | (1,203) | 0
Discount, RMBS subrogation | 4 | 0
Discounted RMBS subrogation, before reinsurance | (1,199) | 0
Less: |  |
Gross other subrogation | (10,907) | (12,937)
Discount, other subrogation | 2,731 | 3,961
Discounted other subrogation, before reinsurance | (8,176) | (8,976)
Gross claim liability, net of all subrogation and discounts, before reinsurance | 72,792 | 68,736
Less: Unearned premium reserves | (48,102) | (48,871)
Plus: Loss adjustment expenses reserves | 275 | 629
Claim liability reported on Balance Sheet, before reinsurance | 24,965 | 20,494
Reinsurance recoverable reported on Balance Sheet | $ 104 | $ 85
III [Member] |  |
Schedule of Insured Financial Obligations with Credit Deterioration [Line Items] |  |
Number of policies | Policies | 59 | 63
Remaining weighted-average contract period (in years) | 17 years | 19 years
Gross insured contractual payments outstanding: |  |
Principal | $ 2,440,917 | $ 2,972,615
Interest | 1,619,094 | 1,792,525
Total | 4,060,011 | 4,765,140
Gross undiscounted claim liability | 1,259,532 | 1,595,525
Discount, gross claim liability | 291,056 | 458,805
Gross claim liability before all subrogation and before reinsurance | 968,476 | 1,136,720
Less: |  |
Gross RMBS subrogation | 0 | 0
Discount, RMBS subrogation | 0 | 0
Discounted RMBS subrogation, before reinsurance | 0 | 0
Less: |  |
Gross other subrogation | (502,340) | (526,957)
Discount, other subrogation | 159,858 | 198,643
Discounted other subrogation, before reinsurance | (342,482) | (328,314)
Gross claim liability, net of all subrogation and discounts, before reinsurance | 625,994 | 808,406
Less: Unearned premium reserves | (43,791) | (63,257)
Plus: Loss adjustment expenses reserves | 13,486 | 15,090
Claim liability reported on Balance Sheet, before reinsurance | 595,689 | 760,239
Reinsurance recoverable reported on Balance Sheet | $ 40,904 | $ 59,503
IV [Member] |  |
Schedule of Insured Financial Obligations with Credit Deterioration [Line Items] |  |
Number of policies | Policies | 166 | 157
Remaining weighted-average contract period (in years) | 15 years | 13 years
Gross insured contractual payments outstanding: |  |
Principal | $ 8,662,183 | $ 8,942,730
Interest | 2,342,277 | 2,391,523
Total | 11,004,460 | 11,334,253
Gross undiscounted claim liability | 6,254,134 | 6,339,537
Discount, gross claim liability | 645,766 | 770,694
Gross claim liability before all subrogation and before reinsurance | 5,608,368 | 5,568,843
Less: |  |
Gross RMBS subrogation | (1,860,701) | (2,841,291)
Discount, RMBS subrogation | 6,827 | 11,716
Discounted RMBS subrogation, before reinsurance | (1,853,874) | (2,829,575)
Less: |  |
Gross other subrogation | (882,664) | (835,078)
Discount, other subrogation | 102,074 | 127,669
Discounted other subrogation, before reinsurance | (780,590) | (707,409)
Gross claim liability, net of all subrogation and discounts, before reinsurance | 2,973,904 | 2,031,859
Less: Unearned premium reserves | (69,434) | (71,848)
Plus: Loss adjustment expenses reserves | 53,526 | 57,479
Claim liability reported on Balance Sheet, before reinsurance | 2,957,996 | 2,017,490
Reinsurance recoverable reported on Balance Sheet | $ (15,334) | $ (17,111)
V [Member] |  |
Schedule of Insured Financial Obligations with Credit Deterioration [Line Items] |  |
Number of policies | Policies | 3 | 3
Remaining weighted-average contract period (in years) | 6 years | 6 years
Gross insured contractual payments outstanding: |  |
Principal | $ 54,590 | $ 54,590
Interest | 16,790 | 16,791
Total | 71,380 | 71,381
Gross undiscounted claim liability | 71,379 | 71,381
Discount, gross claim liability | 4,876 | 6,779
Gross claim liability before all subrogation and before reinsurance | 66,503 | 64,602
Less: |  |
Gross RMBS subrogation | 0 | 0
Discount, RMBS subrogation | 0 | 0
Discounted RMBS subrogation, before reinsurance | 0 | 0
Less: |  |
Gross other subrogation | (13,098) | (13,098)
Discount, other subrogation | 3,353 | 3,978
Discounted other subrogation, before reinsurance | (9,745) | (9,120)
Gross claim liability, net of all subrogation and discounts, before reinsurance | 56,758 | 55,482
Less: Unearned premium reserves | (436) | (455)
Plus: Loss adjustment expenses reserves | 0 | 0
Claim liability reported on Balance Sheet, before reinsurance | 56,322 | 55,027
Reinsurance recoverable reported on Balance Sheet | $ 0 | $ 0

X
- Definition Discounted other subrogation, before reinsurance. + References No definition available. + Details
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- Definition Less Discounted Rmbs Subrogation Before Reinsurance [Abstract] + References No definition available. + Details
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- Definition This element represents the discounting on the gross claim liability for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References No definition available. + Details
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- Definition This element represents the gross undiscounted claim liability for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References No definition available. + Details
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- Definition This element represents the amount of loss adjustment expense reserves represent the costs estimated to be incurred in the settlement of unpaid claims related to financial guarantee insurance contracts and presented in the schedule of insured financial obligations with credit deterioration in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References No definition available. + Details
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- Definition This element represents the discount on the gross subrogation on insured financial obligations with credit deterioration, excluding the discount on the gross subrogation on insured RMBS financial obligations with credit deterioration. + References No definition available. + Details
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- Definition This element represents the discounting on the reduction to gross claim liability for subrogation on insured RMBS financial obligations with credit deterioration. + References No definition available. + Details
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- Definition This element represents the reduction to gross claim liability for subrogation on insured financial obligations with credit deterioration, excluding the reduction to gross claim liability for subrogation on insured RMBS financial obligations with credit deterioration. + References No definition available. + Details
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- Definition This element represents the reduction to gross claim liability for subrogation on insured RMBS financial obligations with credit deterioration. + References No definition available. + Details
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- Definition This element represents the reduction to gross undiscounted claim liability for gross undiscounted subrogation on insured financial obligations with credit deterioration, excluding subrogation on insured RMBS financial obligations with credit deterioration. + References No definition available. + Details
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- Definition This element represents the reduction to gross undiscounted claim liability for gross undiscounted subrogation on insured RMBS financial obligations with credit deterioration. + References No definition available. + Details
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- Definition Remaining weighted average contract period of financial guarantee insurance contracts, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(ii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 + Details
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- Definition This element represents the gross claim liability for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(iv) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
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- Definition This element represents the amount of insured contractual payments outstanding on the underlying insured obligations for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(iii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
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- Definition This element represents the amount of insured contractual payments outstanding attributable to interest accrued on the underlying insured obligations for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(iii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
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- Definition This element represents the amount of insured contractual payments outstanding attributable to the principal of the underlying insured obligations for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(iii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 + Details
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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. + References No definition available. + Details
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- Definition This element represents the net claim liability related to financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(vii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
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- Definition This element represents the number of issued and outstanding contracts for each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(i) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 + Details
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- Definition This element represents the claim liability, reported on or included in the statement of financial position, related to financial guarantee insurance contracts and presented in the schedule of insured financial obligations with credit deterioration in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751140-161288 + Details
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- Definition This element represents the amount of reinsurance recoverable, reported on or included in the statement of financial position, related to financial guarantee insurance contracts and presented in the schedule of insured financial obligations with credit deterioration in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(viii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 + Details
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- Definition This element represents the amount of unearned premium revenue, reported on or included in the statement of financial position, related to financial guarantee insurance contracts and presented in the schedule of insured financial obligations with credit deterioration in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(ix) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
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