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Fair Value Measurements (Tables) | 3 Months Ended
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Mar. 31, 2013
Fair Value Disclosures [Abstract] |
Summary of Carrying Amount and Fair Value of Ambac's Financial Assets and Liabilities | The following table sets forth the carrying amount and fair value of Ambac’s financial assets and liabilities as of March 31, 2013 and December 31, 2012, including the level within the fair value hierarchy at which fair value measurements are categorized. As required by ASC Topic 820, financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement.
|  | Carrying Amount |  |  | Total Fair Value |  |  | Fair Value Measurements Categorized as: |
|  |  | Level 1 |  |  | Level 2 |  |  | Level 3 |
March 31, 2013 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed income securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Municipal obligations |  | $ | 1,794,355 |  |  | $ | 1,794,355 |  |  | $ | — |  |  | $ | 1,794,355 |  |  | $ | — |
Corporate obligations |  |  | 1,069,073 |  |  |  | 1,069,073 |  |  |  | — |  |  |  | 1,065,421 |  |  |  | 3,652 |
Foreign obligations |  |  | 11,878 |  |  |  | 11,878 |  |  |  | — |  |  |  | 11,878 |  |  |  | — |
U.S. government obligations |  |  | 98,312 |  |  |  | 98,312 |  |  |  | 98,312 |  |  |  | — |  |  |  | — |
U.S. agency obligations |  |  | 53,975 |  |  |  | 53,975 |  |  |  | — |  |  |  | 53,975 |  |  |  | — |
Residential mortgage-backed securities |  |  | 1,536,889 |  |  |  | 1,536,889 |  |  |  | — |  |  |  | 1,536,889 |  |  |  | — |
Collateralized debt obligations |  |  | 27,357 |  |  |  | 27,357 |  |  |  | — |  |  |  | 23,452 |  |  |  | 3,905 |
Other asset-backed securities |  |  | 810,451 |  |  |  | 810,451 |  |  |  | — |  |  |  | 760,217 |  |  |  | 50,234 |
Fixed income securities, pledged as collateral: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. government obligations |  |  | 228,228 |  |  |  | 228,228 |  |  |  | 228,228 |  |  |  | — |  |  |  | — |
Short term investments |  |  | 767,932 |  |  |  | 767,932 |  |  |  | 765,379 |  |  |  | 2,553 |  |  |  | — |
Other investments |  |  | 113,812 |  |  |  | 113,812 |  |  |  | — |  |  |  | 113,712 |  |  |  | 100 |
Cash |  |  | 53,135 |  |  |  | 53,135 |  |  |  | 53,135 |  |  |  | — |  |  |  | — |
Loans |  |  | 8,691 |  |  |  | 7,119 |  |  |  | — |  |  |  | — |  |  |  | 7,119 |
Derivative assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate swaps—asset position |  |  | 112,811 |  |  |  | 112,811 |  |  |  | — |  |  |  | 112,811 |  |  |  | — |
Interest rate swaps—liability position |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Futures contracts |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Other assets |  |  | 14,230 |  |  |  | 14,230 |  |  |  | — |  |  |  | — |  |  |  | 14,230 |
Variable interest entity assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed income securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate obligations |  |  | 2,414,607 |  |  |  | 2,414,607 |  |  |  | — |  |  |  | — |  |  |  | 2,414,607 |
Restricted cash |  |  | 2,258 |  |  |  | 2,258 |  |  |  | 2,258 |  |  |  | — |  |  |  | — |
Loans |  |  | 14,327,840 |  |  |  | 14,318,834 |  |  |  | — |  |  |  | 202,023 |  |  |  | 14,116,811 |
Total financial assets |  | $ | 23,445,834 |  |  | $ | 23,435,256 |  |  | $ | 1,147,312 |  |  | $ | 5,677,286 |  |  | $ | 16,610,658 |
Financial liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Obligations under investment and repurchase agreements |  | $ | 363,297 |  |  | $ | 362,208 |  |  | $ | — |  |  | $ | — |  |  | $ | 362,208 |
Liabilities subject to compromise |  |  | 1,690,312 |  |  |  | 909,138 |  |  |  | — |  |  |  | 909,138 |  |  |  | — |
Long term debt, including accrued interest |  |  | 399,505 |  |  |  | 1,110,259 |  |  |  | — |  |  |  | — |  |  |  | 1,110,259 |
Derivative liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit derivatives |  |  | 203,307 |  |  |  | 203,307 |  |  |  | — |  |  |  | — |  |  |  | 203,307 |
Interest rate swaps—asset position |  |  | (65,636 | ) |  |  | (65,636 | ) |  |  | — |  |  |  | (65,636 | ) |  |  | — |
Interest rate swaps—liability position |  |  | 366,949 |  |  |  | 366,949 |  |  |  | — |  |  |  | 241,567 |  |  |  | 125,382 |
Futures contracts |  |  | 911 |  |  |  | 911 |  |  |  | 911 |  |  |  | — |  |  |  | — |
Other contracts |  |  | 215 |  |  |  | 215 |  |  |  | — |  |  |  | 215 |  |  |  | — |
Liabilities for net financial guarantees written |  |  | 6,921,299 |  |  |  | 4,576,031 |  |  |  | — |  |  |  | — |  |  |  | 4,576,031 |
Variable interest entity liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  | 14,229,373 |  |  |  | 14,207,206 |  |  |  | — |  |  |  | 12,296,617 |  |  |  | 1,910,589 |
Derivative liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate swaps—liability position |  |  | 2,231,863 |  |  |  | 2,231,863 |  |  |  | — |  |  |  | 2,231,863 |  |  |  | — |
Currency swaps—liability position |  |  | 85,762 |  |  |  | 85,762 |  |  |  | — |  |  |  | 85,762 |  |  |  | — |
Total financial liabilities |  | $ | 26,427,157 |  |  | $ | 23,988,213 |  |  | $ | 911 |  |  | $ | 15,699,526 |  |  | $ | 8,287,776 |
|  | Carrying Amount |  |  | Total Fair Value |  |  | Fair Value Measurements Categorized as: |
|  |  | Level 1 |  |  | Level 2 |  |  | Level 3 |
December 31, 2012 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed income securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Municipal obligations |  | $ | 1,848,932 |  |  | $ | 1,848,932 |  |  | $ | — |  |  | $ | 1,848,932 |  |  | $ | — |
Corporate obligations |  |  | 1,077,972 |  |  |  | 1,077,972 |  |  |  | — |  |  |  | 1,074,316 |  |  |  | 3,656 |
Foreign obligations |  |  | 70,112 |  |  |  | 70,112 |  |  |  | — |  |  |  | 70,112 |  |  |  | — |
U.S. government obligations |  |  | 127,283 |  |  |  | 127,283 |  |  |  | 127,283 |  |  |  | — |  |  |  | — |
U.S. agency obligations |  |  | 82,535 |  |  |  | 82,535 |  |  |  | — |  |  |  | 82,535 |  |  |  | — |
Residential mortgage-backed securities |  |  | 1,455,582 |  |  |  | 1,455,582 |  |  |  | — |  |  |  | 1,455,582 |  |  |  | — |
Collateralized debt obligations |  |  | 33,342 |  |  |  | 33,342 |  |  |  | — |  |  |  | 26,860 |  |  |  | 6,482 |
Other asset-backed securities |  |  | 706,637 |  |  |  | 706,637 |  |  |  | — |  |  |  | 656,373 |  |  |  | 50,264 |
Fixed income securities, pledged as collateral: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. government obligations |  |  | 265,779 |  |  |  | 265,779 |  |  |  | 265,779 |  |  |  | — |  |  |  | — |
Short term investments |  |  | 661,658 |  |  |  | 661,658 |  |  |  | 657,886 |  |  |  | 3,772 |  |  |  | — |
Other investments |  |  | 100 |  |  |  | 100 |  |  |  | — |  |  |  | — |  |  |  | 100 |
Cash |  |  | 43,837 |  |  |  | 43,837 |  |  |  | 43,837 |  |  |  | — |  |  |  | — |
Loans |  |  | 9,203 |  |  |  | 7,387 |  |  |  | — |  |  |  | — |  |  |  | 7,387 |
Derivative assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate swaps—asset position |  |  | 124,853 |  |  |  | 124,853 |  |  |  | — |  |  |  | 124,853 |  |  |  | — |
Interest rate swaps—liability position |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Futures contracts |  |  | 1,253 |  |  |  | 1,253 |  |  |  | 1,253 |  |  |  | — |  |  |  | — |
Other assets |  |  | 14,557 |  |  |  | 14,557 |  |  |  | — |  |  |  | — |  |  |  | 14,557 |
Variable interest entity assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed income securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate obligations |  |  | 2,261,294 |  |  |  | 2,261,294 |  |  |  | — |  |  |  | — |  |  |  | 2,261,294 |
Restricted cash |  |  | 2,290 |  |  |  | 2,290 |  |  |  | 2,290 |  |  |  | — |  |  |  | — |
Loans |  |  | 15,568,711 |  |  |  | 15,560,051 |  |  |  | — |  |  |  | 200,978 |  |  |  | 15,359,073 |
Total financial assets |  | $ | 24,355,930 |  |  | $ | 24,345,454 |  |  | $ | 1,098,328 |  |  | $ | 5,544,313 |  |  | $ | 17,702,813 |
Financial liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Obligations under investment and repurchase agreements |  | $ | 362,017 |  |  | $ | 361,905 |  |  | $ | — |  |  | $ | — |  |  | $ | 361,905 |
Liabilities subject to compromise |  |  | 1,690,312 |  |  |  | 434,823 |  |  |  | — |  |  |  | 434,823 |  |  |  | — |
Long term debt, including accrued interest |  |  | 377,524 |  |  |  | 801,277 |  |  |  | — |  |  |  | — |  |  |  | 801,277 |
Derivative liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit derivatives |  |  | 213,585 |  |  |  | 213,585 |  |  |  | — |  |  |  | — |  |  |  | 213,585 |
Interest rate swaps—asset position |  |  | (73,264 | ) |  |  | (73,264 | ) |  |  | — |  |  |  | (73,264 | ) |  |  | — |
Interest rate swaps—liability position |  |  | 390,774 |  |  |  | 390,774 |  |  |  | — |  |  |  | 282,022 |  |  |  | 108,752 |
Futures contracts |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Other contracts |  |  | 220 |  |  |  | 220 |  |  |  | — |  |  |  | 220 |  |  |  | — |
Liabilities for net financial guarantees written |  |  | 7,074,808 |  |  |  | 3,091,257 |  |  |  | — |  |  |  | — |  |  |  | 3,091,257 |
Variable interest entity liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  | 15,436,008 |  |  |  | 15,414,233 |  |  |  | — |  |  |  | 12,457,732 |  |  |  | 2,956,501 |
Derivative liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate swaps—liability position |  |  | 2,131,315 |  |  |  | 2,131,315 |  |  |  | — |  |  |  | 2,131,315 |  |  |  | — |
Currency swaps—liability position |  |  | 90,466 |  |  |  | 90,466 |  |  |  | — |  |  |  | 90,466 |  |  |  | — |
Total financial liabilities |  | $ | 27,693,765 |  |  | $ | 22,856,591 |  |  | $ | — |  |  | $ | 15,323,314 |  |  | $ | 7,533,277 |
Information about Valuation Inputs for Fixed Income Securities Classified as Level 3 | Significant inputs for the interest only strips valuation at March 31, 2013 and December 31, 2012 include the following weighted averages: March 31, 2013
| a. | Coupon rate: 0.345%
| b. | Maturity: 20.89 years
| c. | Yield: 6.03%
December 31, 2012
| a. | Coupon rate: 0.345%
| b. | Maturity: 21.14 years
| c. | Yield: 6.08%
Collateralized debt obligations (“CDO”): Securities are floating rate senior notes where the underlying securities of the CDO consist of subordinated bank perpetual preferred securities. The fair value of such securities classified as Level 3 was $3,905 and $6,482 at March 31, 2013 and December 31, 2012, respectively. Fair value was calculated using a discounted cash flow approach with expected future cash flows discounted using a yield curve consistent with the security type and rating. Significant inputs for the valuation at March 31, 2013 and December 31, 2012 include the following weighted averages: March 31, 2013
| a. | Coupon rate: 0.85%
| b. | Maturity: 1.24 years
| c. | Yield: 3.85%
December 31, 2012
| a. | Coupon rate: 1.05%
| b. | Maturity: 1.51 years
| c. | Yield: 5.92%
Other asset-backed securities: These securities are floating rate investment grade notes collateralized by various asset types. The fair value of such securities classified as Level 3 was $50,234 and $50,264 at March 31, 2013 and December 31, 2012, respectively. Fair value was calculated using a discounted cash flow approach with expected future cash flows discounted using a yield curve consistent with the security type and rating. Significant inputs for the valuation at March 31, 2013 and December 31, 2012 include the following weighted averages: March 31, 2013
| a. | Coupon rate: 0.69%
| b. | Maturity: 7.62 years
| c. | Yield: 7.50%
December 31, 2012
| a. | Coupon rate: 0.71%
| b. | Maturity: 7.86 years
| c. | Yield: 7.50%
European ABS transactions: The fair value of such obligations classified as Level 3 was $1,910,589 and $2,956,501 at March 31, 2013 and December 31, 2012, respectively. Fair values were calculated by using a discounted cash flow approach. The discount rates used were based on the rates implied from the third party quoted values (Level 2) for comparable notes from the same securitization. Significant inputs for the valuation at March 31, 2013 and December 31, 2012 include the following weighted averages: March 31, 2013
| a. | Coupon rate: 1.59%
| b. | Maturity: 18.26 years
| c. | Yield: 3.98%
December 31, 2012
| a. | Coupon rate: 1.64%
| b. | Maturity: 12.34 years
| c. | Yield: 4.02%
Summary of Information about Described Model Inputs Used to Determine Fair Value of Each Class of Credit Derivatives | Information about the above described model inputs used to determine the fair value of each class of credit derivatives, including the CVA as a percentage of the gross mark-to-market liability before considering Ambac credit risk (“CVA percentage”), as of March 31, 2013 and December 31, 2012 is summarized below: As of March 31, 2013
|  | CLOs |  |  | Other(1) |
Notional outstanding |  | $ | 5,702,366 |  |  | $ | 3,238,742 |
Weighted average reference obligation price |  |  | 97.4 |  |  |  | 86.9 |
Weighted average life (WAL) in years |  |  | 2.1 |  |  |  | 4.5 |
Weighted average credit rating |  |  | AA- |  |  |  | A |
Weighted average relative change ratio |  |  | 34.5 | % |  |  | 37.8 | %
CVA percentage |  |  | 41.4 | % |  |  | 49.4 | %
Fair value of derivative liabilities |  | $ | (30,736 | ) |  | $ | (115,014 | )
As of December 31, 2012
|  | CLOs |  |  | Other(1) |
Notional outstanding |  | $ | 6,155,767 |  |  | $ | 3,701,387 |
Weighted average reference obligation price |  |  | 96.5 |  |  |  | 86.9 |
Weighted average life (WAL) in years |  |  | 2.2 |  |  |  | 4.2 |
Weighted average credit rating |  |  | AA- |  |  |  | A |
Weighted average relative change ratio |  |  | 34.4 | % |  |  | 38.2 | %
CVA percentage |  |  | 55.0 | % |  |  | 55.0 | %
Fair value of derivative liabilities |  | $ | (34,645 | ) |  | $ | (116,086 | )
(1) | Excludes contracts for which fair values are based on credit derivative quotes rather than reference obligation quotes. Such contracts have a combined notional outstanding of $1,263,630, WAL of 7.5 years and liability fair value of ($57,557) as of March 31, 2013. Other inputs to the valuation of these transactions at March 31, 2013 include weighted average quotes of 9% of notional, weighted average rating of A and Ambac CVA percentage of 50.0%. As of December 31, 2012, these contracts had a combined notional outstanding of $1,424,623, WAL of 7.9 years and liability fair value of ($62,854). Other inputs to the valuation of these transactions at December 31, 2012 include weighted average quotes of 10% of notional, weighted average rating of A and Ambac CVA percentage of 55.0%.
Summary of Changes in Level 3 Fair Value Category | The following tables present the changes in the Level 3 fair value category for the three months ended March 31, 2013 and 2012. Ambac classifies financial instruments in Level 3 of the fair value hierarchy when there is reliance on at least one significant unobservable input to the valuation model. In addition to these unobservable inputs, the valuation models for Level 3 financial instruments typically also rely on a number of inputs that are readily observable either directly or indirectly. Thus, the gains and losses presented below include changes in the fair value related to both observable and unobservable inputs. Level-3 financial assets and liabilities accounted for at fair value
|  |  |  |  |  |  |  |  |  |  | VIE Assets and Liabilities |  |  |  |
Three months ended March 31, 2013 |  | Investments |  |  | Other assets |  |  | Derivatives |  |  | Investments |  |  | Loans |  |  | Long-term debt |  |  | Total |
Balance, beginning of period |  | $ | 60,402 |  |  | $ | 14,557 |  |  | $ | (322,337 | ) |  | $ | 2,261,294 |  |  | $ | 15,359,073 |  |  | $ | (2,956,501 | ) |  | $ | 14,416,488 |
Additions of VIEs consolidated |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Total gains/(losses) realized and unrealized: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Included in earnings |  |  | (23 | ) |  |  | (327 | ) |  |  | (3,162 | ) |  |  | 297,294 |  |  |  | 400,456 |  |  |  | (127,393 | ) |  |  | 566,845 |
Included in other comprehensive income |  |  | 698 |  |  |  | — |  |  |  | — |  |  |  | (143,981 | ) |  |  | (955,455 | ) |  |  | 193,905 |  |  |  | (904,833 | )
Purchases |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Issuances |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Sales |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Settlements |  |  | (3,286 | ) |  |  | — |  |  |  | (3,190 | ) |  |  | — |  |  |  | (687,263 | ) |  |  | 4,864 |  |  |  | (688,875 | )
Transfers in Level 3 |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Transfers out of Level 3 |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 974,536 |  |  |  | 974,536 |
Deconsolidation of VIEs |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Balance, end of period |  | $ | 57,791 |  |  | $ | 14,230 |  |  | $ | (328,689 | ) |  | $ | 2,414,607 |  |  | $ | 14,116,811 |  |  | $ | (1,910,589 | ) |  | $ | 14,364,161 |
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date |  | $ | — |  |  | $ | (327 | ) |  | $ | (5,684 | ) |  | $ | 297,294 |  |  | $ | 400,456 |  |  | $ | (127,393 | ) |  | $ | 564,346 |
|  |  |  |  |  |  |  |  |  |  | VIE Assets and Liabilities |  |  |  |
Three months ended March 31, 2012 |  | Investments |  |  | Other assets |  |  | Derivatives |  |  | Investments |  |  | Loans |  |  | Long-term debt |  |  | Total |
Balance, beginning of period |  | $ | 97,522 |  |  | $ | 16,779 |  |  | $ | (486,775 | ) |  | $ | 2,199,338 |  |  | $ | 14,126,994 |  |  | $ | (1,934,642 | ) |  | $ | 14,019,216 |
Additions of VIEs consolidated |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Total gains/(losses) realized and unrealized: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Included in earnings |  |  | (49 | ) |  |  | (756 | ) |  |  | 122,327 |  |  |  | (82,816 | ) |  |  | 166,665 |  |  |  | (136,563 | ) |  |  | 68,808 |
Included in other comprehensive income |  |  | 7,814 |  |  |  | — |  |  |  | — |  |  |  | 68,143 |  |  |  | 415,857 |  |  |  | (63,205 | ) |  |  | 428,609 |
Purchases |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Issuances |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Sales |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Settlements |  |  | (2,742 | ) |  |  | — |  |  |  | 8,832 |  |  |  | — |  |  |  | (249,439 | ) |  |  | 13,030 |  |  |  | (230,319 | )
Transfers in Level 3 |  |  | 58,905 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (665,264 | ) |  |  | (606,359 | )
Transfers out of Level 3 |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Deconsolidation of VIEs |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Balance, end of period |  | $ | 161,450 |  |  | $ | 16,023 |  |  | $ | (355,616 | ) |  | $ | 2,184,665 |  |  | $ | 14,460,077 |  |  | $ | (2,786,644 | ) |  | $ | 13,679,955 |
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date |  | $ | — |  |  | $ | (756 | ) |  | $ | 107,245 |  |  | $ | (82,816 | ) |  | $ | 167,146 |  |  | $ | (136,563 | ) |  | $ | 54,256 |
The tables below provide roll-forward information by class of investments and derivatives measured using significant unobservable inputs. Level-3 Investments by class
Three months ended March 31, 2013 |  | Collateralized Debt Obligations |  |  | Other Asset Backed Securities |  |  | Corporate Obligations |  |  | U.S. Agency Obligations |  |  | Total Investments |
Balance, beginning of period |  | $ | 6,482 |  |  | $ | 50,264 |  |  | $ | 3,656 |  |  | $ | — |  |  | $ | 60,402 |
Total gains/(losses) realized and unrealized: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Included in earnings |  |  | (3 | ) |  |  | — |  |  |  | (20 | ) |  |  | — |  |  |  | (23 | )
Included in other comprehensive income |  |  | 113 |  |  |  | 569 |  |  |  | 16 |  |  |  | — |  |  |  | 698 |
Purchases |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Issuances |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Sales |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  |  |
Settlements |  |  | (2,687 | ) |  |  | (599 | ) |  |  | — |  |  |  | — |  |  |  | (3,286 | )
Transfers in Level 3 |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Transfers out of Level 3 |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Balance, end of period |  | $ | 3,905 |  |  | $ | 50,234 |  |  | $ | 3,652 |  |  | $ | — |  |  | $ | 57,791 |
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Level-3 Investments by class
Three months ended March 31, 2012 |  | Collateralized Debt Obligations |  |  | Other Asset Backed Securities |  |  | Corporate Obligations |  |  | U.S. Agency Obligations |  |  | Total Investments |
Balance, beginning of period |  | $ | 12,482 |  |  | $ | 75,886 |  |  | $ | 7,930 |  |  | $ | 1,224 |  |  | $ | 97,522 |
Total gains/(losses) realized and unrealized: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Included in earnings |  |  | (2 | ) |  |  | — |  |  |  | (46 | ) |  |  | (1 | ) |  |  | (49 | )
Included in other comprehensive income |  |  | 101 |  |  |  | 8,072 |  |  |  | (354 | ) |  |  | (5 | ) |  |  | 7,814 |
Purchases |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Issuances |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Sales |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Settlements |  |  | (2,742 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (2,742 | )
Transfers in Level 3 |  |  | — |  |  |  | 53,068 |  |  |  | 5,837 |  |  |  | — |  |  |  | 58,905 |
Transfers out of Level 3 |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Balance, end of period |  | $ | 9,839 |  |  | $ | 137,026 |  |  | $ | 13,367 |  |  | $ | 1,218 |  |  | $ | 161,450 |
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Level-3 Derivatives by class
Three months ended March 31, 2013 |  | Interest Rate Swaps |  |  | Credit Derivatives |  |  | Call Options on Long-term debt |  |  | Total Derivatives |
Balance, beginning of period |  | $ | (108,752 | ) |  | $ | (213,585 | ) |  | $ | — |  |  | $ | (322,337 | )
Additions of VIEs consolidated |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total gains/(losses) realized and unrealized: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Included in earnings |  |  | (15,949 | ) |  |  | 12,787 |  |  |  | — |  |  |  | (3,162 | )
Included in other comprehensive income |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Purchases |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Issuances |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Sales |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Settlements |  |  | (681 | ) |  |  | (2,509 | ) |  |  | — |  |  |  | (3,190 | )
Transfers in Level 3 |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Transfers out of Level 3 |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Deconsolidation of VIEs |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Balance, end of period |  | $ | (125,382 | ) |  | $ | (203,307 | ) |  | $ | — |  |  | $ | (328,689 | )
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date |  | $ | (15,949 | ) |  | $ | 10,265 |  |  | $ | — |  |  | $ | (5,684 | )
Level-3 Derivatives by class
Three months ended March 31, 2012 |  | Interest Rate Swaps |  |  | Credit Derivatives |  |  | Call Options on Long-term debt |  |  | Total Derivatives |
Balance, beginning of period |  | $ | (302,177 | ) |  | $ | (190,653 | ) |  | $ | 6,055 |  |  | $ | (486,775 | )
Additions of VIEs for ASC 2009-17 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total gains/(losses) realized and unrealized: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Included in earnings |  |  | 67,869 |  |  |  | (7,222 | ) |  |  | 61,680 |  |  |  | 122,327 |
Included in other comprehensive income |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Purchases |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Issuances |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Sales |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Settlements |  |  | 12,086 |  |  |  | (3,254 | ) |  |  | — |  |  |  | 8,832 |
Transfers in Level 3 |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Transfers out of Level 3 |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Deconsolidation of VIEs |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Balance, end of period |  | $ | (222,222 | ) |  | $ | (201,129 | ) |  | $ | 67,735 |  |  | $ | (355,616 | )
The amount of total gains/(losses) included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date |  | $ | 61,598 |  |  | $ | (16,033 | ) |  | $ | 61,680 |  |  | $ | 107,245 |
Summary of Gains and Losses (Realized and Unrealized) Relating to Level 3 Assets and Liabilities Included in Earnings | Gains and losses (realized and unrealized) relating to Level 3 assets and liabilities included in earnings for the three months ended March 31, 2013 and 2012 are reported as follows:
|  | Net investment income |  |  | Realized gains or (losses) and other settlements on credit derivative contracts |  |  | Unrealized gains or (losses) on credit derivative contracts |  |  | Derivative products revenues (interest rate swaps) |  |  | Income on variable interest entities |  |  | Other income |
Three months ended 2013 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total gains or losses included in earnings for the period |  | $ | (23 | ) |  | $ | 2,509 |  |  | $ | 10,278 |  |  | $ | (15,949 | ) |  | $ | 570,357 |  |  | $ | (327 | )
Changes in unrealized gains or losses relating to the assets and liabilities still held at the reporting date |  |  | — |  |  |  | — |  |  |  | 10,266 |  |  |  | (15,949 | ) |  |  | 570,357 |  |  |  | (327 | )
Three months ended 2012 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total gains or losses included in earnings for the period |  | $ | (49 | ) |  | $ | 3,254 |  |  | $ | (10,476 | ) |  | $ | 67,869 |  |  | $ | (52,714 | ) |  | $ | 60,924 |
Changes in unrealized gains or losses relating to the assets and liabilities still held at the reporting date |  |  | — |  |  |  | — |  |  |  | (16,033 | ) |  |  | 61,598 |  |  |  | (52,233 | ) |  |  | 60,924 |

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