Insurance Regulatory Restrictions	12 Months Ended
Dec. 31, 2011
Insurance Regulatory Restrictions [Abstract]
Insurance Regulatory Restrictions	7 INSURANCE REGULATORY RESTRICTIONS Ambac Assurance (exclusive of the Segregated Account which is under the control of OCI via the Segregated Account Rehabilitation Plan) and Everspan are subject to the insurance laws and regulations of each jurisdiction in which it is licensed, some of which are described below. Failure to comply with applicable insurance laws and regulations (including, without limitation, minimum surplus requirements, aggregate risk limits and single risk limits) could expose Ambac Assurance or Everspan to fines, the loss or suspension of insurance licenses in certain jurisdictions, the imposition of orders by regulators with respect to the conduct of business by and/or the inability to pay dividends, all of which could have an adverse impact on our business results and prospects. New York's comprehensive financial guarantee insurance law defines the scope of permitted financial guarantee insurance and governs the conduct of business of all financial guarantors licensed to do business in New York, including Ambac Assurance. The New York financial guarantee insurance law also establishes single risk and aggregate limits with respect to insured obligations insured by financial guarantee insurers. Such single risk limits are specific to the type of insured obligation (for example, municipal or asset-backed). Under the aggregate limits, policyholders' surplus and contingency reserves must at least equal a percentage of aggregate net financial guarantee liability that is equal to the sum of various percentages of aggregate net liability for various categories of specified obligations. Wisconsin laws and regulations applicable to financial guarantors, as well as the laws of several other states, are less comprehensive than New York law and relate primarily to single and aggregate risk limits. As a result of decreased statutory capital resulting from the significant losses experienced by Ambac Assurance, Ambac Assurance is not in compliance with its regulatory single and aggregate risk limits. Through run-off of the portfolio, Ambac Assurance will seek to reduce its exposure to no more than the permitted amounts, but may not be able to do so. Everspan is in compliance with all of such limits. Ambac Assurance's ability to pay dividends is generally restricted by law and subject to approval by OCI. Wisconsin insurance law restricts the payment of dividends in any 12-month period without regulatory approval to the lesser of (a) 10% of policyholders' surplus as of the preceding December 31, and (b) the greater of (i) statutory net income (loss) for the calendar year preceding the date of dividend, minus realized capital gains for that calendar year or (ii) the aggregate of statutory net income (loss) for three calendar years preceding the date of the dividend, minus realized capital gains for those calendar years and minus dividends paid or credited within the first two of the three preceding calendar years. In connection with the termination of reinsurance contracts, OCI requires adjustments to the dividend calculation for any surplus or net income gains recognized. Additionally, no quarterly dividend may exceed the dividend paid in the corresponding quarter of the preceding year by more than 15% without notifying OCI 30 days in advance of payment. Based upon these restrictions, at December 31, 2011, Ambac Assurance will not be able to pay common stock dividends during 2012 without regulatory approval. Ambac Assurance did not pay cash dividends on its common stock in 2011 or 2010. Ambac Assurance's statutory financial statements are prepared on the basis of accounting practices prescribed or permitted by OCI. OCI recognizes only statutory accounting practices prescribed or permitted by the State of Wisconsin for determining and reporting the financial condition and results of operations of an insurance company for determining its solvency under Wisconsin Insurance Law. The National Association of Insurance Commissioners ("NAIC") Accounting Practices and Procedures manual ("NAIC SAP") has been adopted as a component of prescribed practices by the State of Wisconsin. Statutory capital and surplus was $495,293 (unaudited) and $1,026,920 at December 31, 2011 and 2010, respectively. Qualified statutory capital was $688,032 (unaudited) and $1,539,524 at December 31, 2011 and 2010, respectively. Statutory net loss for Ambac Assurance was $835,795 (unaudited) and $1,372,218 for 2011 and 2010, respectively. Statutory capital and surplus differs from stockholders' equity determined under GAAP principally due to statutory accounting rules that treat loss reserves, consolidation of subsidiaries, premiums earned, policy acquisition costs and deferred income taxes differently. OCI has prescribed an accounting practice that differs from NAIC SAP. Paragraph 7 of Statement of Statutory Accounting Principles No. 60 "Financial Guaranty Insurance" ("SSAP 60") allows for a deduction from loss reserves for the time value of money by application of a discount rate equal to the average rate of return on the admitted assets of the financial guaranty insurer as of the date of the computation of the reserve. The discount rate shall be adjusted at the end of each calendar year. Additionally, in accordance with paragraph 7 of Statutory Accounting Principles No. 5 "Liabilities, Contingencies and Impairments of Assets", Ambac Assurance records probable losses on its subsidiaries credit derivative contracts, using a discount rate equal to the average rate of return on its admitted assets. The Company's average rates of return on its admitted assets at December 31, 2011 and December 31, 2010 were 7.45% and 7.06%, respectively. OCI has directed the Company to utilize a prescribed discount rate of 5.10% for the purpose of discounting both its loss reserves and its estimated impairment losses on subsidiary guarantees. Statutory surplus at December 31, 2011 and December 31, 2010 was lower by $98,225 and $35,233, respectively, than if the Company had reported such amounts in accordance with NAIC SAP. OCI has prescribed an additional accounting practice that differs from NAIC SAP. Paragraph 4 of Statement of Statutory Accounting Principles No. 41 "Surplus Notes" ("SSAP 41") states that proceeds received by the issuer of surplus notes must be in the form of cash or other admitted assets having readily determinable values and liquidity satisfactory to the commissioner of the state of domicile. Under the statutory accounting principles as generally applied, surplus notes issued in conjunction with commutations or the settlement of claims would be valued at zero upon issuance pursuant to paragraph 4, SSAP 41. OCI has directed the Company to record surplus notes issued in connection with commutations or the settlement of claims at full par value upon issuance as in these instances the surplus notes do not represent a contribution of capital, but rather a distribution of value from the common and preferred shareholders of the Company. The surplus notes issued in connection with commutations or settlement of claims has a claim against surplus senior to the preferred and common shareholders. Statutory surplus is not impacted as a result of the prescribed practice as it is a reclassification from unassigned funds to surplus notes. OCI has extended the preceding prescribed practice related to surplus notes to the evaluation of other-than-temporary impairments for Ambac Assurance guaranteed securities held in the investment portfolio. Paragraph 35 of Statement of Statutory Accounting Principles No. 43R "Loan-backed and Structured Securities" states that when an other-than-temporary impairment has occurred, the amount of the other-than-temporary impairment recognized as a realized loss shall equal the difference between the investment's amortized cost basis and the present value of cash flows expected to be collected, discounted at the loan-backed or structured security's effective interest rate. Under NAIC SAP, the present value of cash flows expected to be collected should include the fair value of surplus notes received from Ambac Assurance, as required under the confirmed Segregated Account Rehabilitation Plan. OCI has prescribed an accounting practice that differs from NAIC and has directed the Company to utilize par value rather than fair value of these surplus notes in this computation. Statutory surplus at December 31, 2011 and December 31, 2010 is greater by $84,344 and $76,709, respectively, than if the present value of the cash flows expected to be collected included the surplus notes at fair value in accordance with NAIC SAP. Wisconsin accounting practices for changes to contingency reserves differ from NAIC SAP. Under NAIC SAP, contributions to and releases from the contingency reserve are recorded via a direct charge or credit to surplus. Under section 3.08(7)(b) of the Wisconsin Administrative Code, contributions to and releases from the contingency reserve are to be recorded through underwriting income. The Company received permission from OCI to record contributions to and releases from the contingency reserve and the related tax and loss bond impact, in accordance with NAIC SAP. Statutory surplus is the same using each of these accounting practices.

7 INSURANCE REGULATORY RESTRICTIONS

Ambac Assurance (exclusive of the Segregated Account which is under the control of OCI via the Segregated Account Rehabilitation Plan) and Everspan are subject to the insurance laws and regulations of each jurisdiction in which it is licensed, some of which are described below. Failure to comply with applicable insurance laws and regulations (including, without limitation, minimum surplus requirements, aggregate risk limits and single risk limits) could expose Ambac Assurance or Everspan to fines, the loss or suspension of insurance licenses in certain jurisdictions, the imposition of orders by regulators with respect to the conduct of business by and/or the inability to pay dividends, all of which could have an adverse impact on our business results and prospects.

New York's comprehensive financial guarantee insurance law defines the scope of permitted financial guarantee insurance and governs the conduct of business of all financial guarantors licensed to do business in New York, including Ambac Assurance. The New York financial guarantee insurance law also establishes single risk and aggregate limits with respect to insured obligations insured by financial guarantee insurers. Such single risk limits are specific to the type of insured obligation (for example, municipal or asset-backed). Under the aggregate limits, policyholders' surplus and contingency reserves must at least equal a percentage of aggregate net financial guarantee liability that is equal to the sum of various percentages of aggregate net liability for various categories of specified obligations. Wisconsin laws and regulations applicable to financial guarantors, as well as the laws of several other states, are less comprehensive than New York law and relate primarily to single and aggregate risk limits.

As a result of decreased statutory capital resulting from the significant losses experienced by Ambac Assurance, Ambac Assurance is not in compliance with its regulatory single and aggregate risk limits. Through run-off of the portfolio, Ambac Assurance will seek to reduce its exposure to no more than the permitted amounts, but may not be able to do so. Everspan is in compliance with all of such limits.

Ambac Assurance's ability to pay dividends is generally restricted by law and subject to approval by OCI. Wisconsin insurance law restricts the payment of dividends in any 12-month period without regulatory approval to the lesser of (a) 10% of policyholders' surplus as of the preceding December 31, and (b) the greater of (i) statutory net income (loss) for the calendar year preceding the date of dividend, minus realized capital gains for that calendar year or (ii) the aggregate of statutory net income (loss) for three calendar years preceding the date of the dividend, minus realized capital gains for those calendar years and minus dividends paid or credited within the first two of the three preceding calendar years. In connection with the termination of reinsurance contracts, OCI requires adjustments to the dividend calculation for any surplus or net income gains recognized. Additionally, no quarterly dividend may exceed the dividend paid in the corresponding quarter of the preceding year by more than 15% without notifying OCI 30 days in advance of payment. Based upon these restrictions, at December 31, 2011, Ambac Assurance will not be able to pay common stock dividends during 2012 without regulatory approval. Ambac Assurance did not pay cash dividends on its common stock in 2011 or 2010.

Ambac Assurance's statutory financial statements are prepared on the basis of accounting practices prescribed or permitted by OCI. OCI recognizes only statutory accounting practices prescribed or permitted by the State of Wisconsin for determining and reporting the financial condition and results of operations of an insurance company for determining its solvency under Wisconsin Insurance Law. The National Association of Insurance Commissioners ("NAIC") Accounting Practices and Procedures manual ("NAIC SAP") has been adopted as a component of prescribed practices by the State of Wisconsin.

Statutory capital and surplus was $495,293 (unaudited) and $1,026,920 at December 31, 2011 and 2010, respectively. Qualified statutory capital was $688,032 (unaudited) and $1,539,524 at December 31, 2011 and 2010, respectively. Statutory net loss for Ambac Assurance was $835,795 (unaudited) and $1,372,218 for 2011 and 2010, respectively. Statutory capital and surplus differs from stockholders' equity determined under GAAP principally due to statutory accounting rules that treat loss reserves, consolidation of subsidiaries, premiums earned, policy acquisition costs and deferred income taxes differently.

OCI has prescribed an accounting practice that differs from NAIC SAP. Paragraph 7 of Statement of Statutory Accounting Principles No. 60 "Financial Guaranty Insurance" ("SSAP 60") allows for a deduction from loss reserves for the time value of money by application of a discount rate equal to the average rate of return on the admitted assets of the financial guaranty insurer as of the date of the computation of the reserve. The discount rate shall be adjusted at the end of each calendar year. Additionally, in accordance with paragraph 7 of Statutory Accounting Principles No. 5 "Liabilities, Contingencies and Impairments of Assets", Ambac Assurance records probable losses on its subsidiaries credit derivative contracts, using a discount rate equal to the average rate of return on its admitted assets. The Company's average rates of return on its admitted assets at December 31, 2011 and December 31, 2010 were 7.45% and 7.06%, respectively. OCI has directed the Company to utilize a prescribed discount rate of 5.10% for the purpose of discounting both its loss reserves and its estimated impairment losses on subsidiary guarantees. Statutory surplus at December 31, 2011 and December 31, 2010 was lower by $98,225 and $35,233, respectively, than if the Company had reported such amounts in accordance with NAIC SAP.

OCI has prescribed an additional accounting practice that differs from NAIC SAP. Paragraph 4 of Statement of Statutory Accounting Principles No. 41 "Surplus Notes" ("SSAP 41") states that proceeds received by the issuer of surplus notes must be in the form of cash or other admitted assets having readily determinable values and liquidity satisfactory to the commissioner of the state of domicile. Under the statutory accounting principles as generally applied, surplus notes issued in conjunction with commutations or the settlement of claims would be valued at zero upon issuance pursuant to paragraph 4, SSAP 41. OCI has directed the Company to record surplus notes issued in connection with commutations or the settlement of claims at full par value upon issuance as in these instances the surplus notes do not represent a contribution of capital, but rather a distribution of value from the common and preferred shareholders of the Company. The surplus notes issued in connection with commutations or settlement of claims has a claim against surplus senior to the preferred and common shareholders. Statutory surplus is not impacted as a result of the prescribed practice as it is a reclassification from unassigned funds to surplus notes.

OCI has extended the preceding prescribed practice related to surplus notes to the evaluation of other-than-temporary impairments for Ambac Assurance guaranteed securities held in the investment portfolio. Paragraph 35 of Statement of Statutory Accounting Principles No. 43R "Loan-backed and Structured Securities" states that when an other-than-temporary impairment has occurred, the amount of the other-than-temporary impairment recognized as a realized loss shall equal the difference between the investment's amortized cost basis and the present value of cash flows expected to be collected, discounted at the loan-backed or structured security's effective interest rate. Under NAIC SAP, the present value of cash flows expected to be collected should include the fair value of surplus notes received from Ambac Assurance, as required under the confirmed Segregated Account Rehabilitation Plan. OCI has prescribed an accounting practice that differs from NAIC and has directed the Company to utilize par value rather than fair value of these surplus notes in this computation. Statutory surplus at December 31, 2011 and December 31, 2010 is greater by $84,344 and $76,709, respectively, than if the present value of the cash flows expected to be collected included the surplus notes at fair value in accordance with NAIC SAP.

Wisconsin accounting practices for changes to contingency reserves differ from NAIC SAP. Under NAIC SAP, contributions to and releases from the contingency reserve are recorded via a direct charge or credit to surplus. Under section 3.08(7)(b) of the Wisconsin Administrative Code, contributions to and releases from the contingency reserve are to be recorded through underwriting income. The Company received permission from OCI to record contributions to and releases from the contingency reserve and the related tax and loss bond impact, in accordance with NAIC SAP. Statutory surplus is the same using each of these accounting practices.