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Investments (Tables) | 9 Months Ended
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Sep. 30, 2023
Investments, Debt and Equity Securities [Abstract] |
Schedule of Debt and Equity Securities Reconciliation | The following tables present the composition of our investment portfolio by major security type. Our securities are reported in our consolidated balance sheets at fair value. The changes in fair value for our fixed-maturity securities (other than hybrid securities) are reported as a component of accumulated other comprehensive income (loss), net of deferred income taxes, in our consolidated balance sheets. The net holding period gains (losses) reported below represent the inception-to-date changes in fair value for the hybrid and equity securities. The changes in the net holding period gains (losses) between periods are recorded as a component of net realized gains (losses) on securities in our consolidated statements of comprehensive income.
($ in millions) | Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Net Holding Period Gains (Losses) |  | Fair Value |  | % of Total Fair Value
September 30, 2023 |  |  |  |  |  |  |  |  |  |  |
Available-for-sale securities: |  |  |  |  |  |  |  |  |  |  |
Fixed maturities: |  |  |  |  |  |  |  |  |  |  |
U.S. government obligations | $ | 36,392.2 |  |  | $ | 0 |  |  | $ | (2,098.4) |  |  | $ | 0 |  |  | $ | 34,293.8 |  |  | 55.4 | %
State and local government obligations | 2,257.6 |  |  | 0 |  |  | (203.3) |  |  | 0 |  |  | 2,054.3 |  |  | 3.3 |
Foreign government obligations | 16.9 |  |  | 0 |  |  | (1.5) |  |  | 0 |  |  | 15.4 |  |  | 0.1 |
Corporate debt securities | 10,880.8 |  |  | 1.3 |  |  | (591.8) |  |  | (36.1) |  |  | 10,254.2 |  |  | 16.6 |
Residential mortgage-backed securities | 530.4 |  |  | 0.2 |  |  | (13.0) |  |  | (1.8) |  |  | 515.8 |  |  | 0.8 |
Commercial mortgage-backed securities | 4,699.5 |  |  | 2.1 |  |  | (723.9) |  |  | 0 |  |  | 3,977.7 |  |  | 6.4 |
Other asset-backed securities | 5,524.2 |  |  | 0.1 |  |  | (210.1) |  |  | (0.6) |  |  | 5,313.6 |  |  | 8.6 |
Redeemable preferred stocks | 189.0 |  |  | 0 |  |  | (4.3) |  |  | (17.6) |  |  | 167.1 |  |  | 0.3 |
Total fixed maturities | 60,490.6 |  |  | 3.7 |  |  | (3,846.3) |  |  | (56.1) |  |  | 56,591.9 |  |  | 91.5 |
Short-term investments | 1,795.2 |  |  | 0 |  |  | 0 |  |  | 0 |  |  | 1,795.2 |  |  | 2.9 |
Total available-for-sale securities | 62,285.8 |  |  | 3.7 |  |  | (3,846.3) |  |  | (56.1) |  |  | 58,387.1 |  |  | 94.4 |
Equity securities: |  |  |  |  |  |  |  |  |  |  |
Nonredeemable preferred stocks | 976.9 |  |  | 0 |  |  | 0 |  |  | (108.0) |  |  | 868.9 |  |  | 1.4 |
Common equities | 662.6 |  |  | 0 |  |  | 0 |  |  | 1,951.9 |  |  | 2,614.5 |  |  | 4.2 |
Total equity securities | 1,639.5 |  |  | 0 |  |  | 0 |  |  | 1,843.9 |  |  | 3,483.4 |  |  | 5.6 |
Total portfolio 1 | $ | 63,925.3 |  |  | $ | 3.7 |  |  | $ | (3,846.3) |  |  | $ | 1,787.8 |  |  | $ | 61,870.5 |  |  | 100.0 | %
($ in millions) | Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Net Holding Period Gains (Losses) |  | Fair Value |  | % of Total Fair Value
September 30, 2022 |  |  |  |  |  |  |  |  |  |  |
Available-for-sale securities: |  |  |  |  |  |  |  |  |  |  |
Fixed maturities: |  |  |  |  |  |  |  |  |  |  |
U.S. government obligations | $ | 24,260.9 |  |  | $ | 0 |  |  | $ | (1,855.4) |  |  | $ | 0 |  |  | $ | 22,405.5 |  |  | 42.8 | %
State and local government obligations | 2,140.9 |  |  | 0 |  |  | (215.4) |  |  | 0 |  |  | 1,925.5 |  |  | 3.7 |
Foreign government obligations | 16.7 |  |  | 0 |  |  | (1.4) |  |  | 0 |  |  | 15.3 |  |  | 0.1 |
Corporate debt securities | 10,119.8 |  |  | 0 |  |  | (832.5) |  |  | (58.9) |  |  | 9,228.4 |  |  | 17.6 |
Residential mortgage-backed securities | 754.2 |  |  | 0.4 |  |  | (16.5) |  |  | (15.1) |  |  | 723.0 |  |  | 1.4 |
Commercial mortgage-backed securities | 5,833.9 |  |  | 1.4 |  |  | (747.4) |  |  | 0 |  |  | 5,087.9 |  |  | 9.7 |
Other asset-backed securities | 4,876.7 |  |  | 0 |  |  | (268.9) |  |  | (1.9) |  |  | 4,605.9 |  |  | 8.8 |
Redeemable preferred stocks | 202.6 |  |  | 0 |  |  | (5.6) |  |  | (15.4) |  |  | 181.6 |  |  | 0.3 |
Total fixed maturities | 48,205.7 |  |  | 1.8 |  |  | (3,943.1) |  |  | (91.3) |  |  | 44,173.1 |  |  | 84.4 |
Short-term investments | 4,237.6 |  |  | 0 |  |  | 0 |  |  | 0 |  |  | 4,237.6 |  |  | 8.1 |
Total available-for-sale securities | 52,443.3 |  |  | 1.8 |  |  | (3,943.1) |  |  | (91.3) |  |  | 48,410.7 |  |  | 92.5 |
Equity securities: |  |  |  |  |  |  |  |  |  |  |
Nonredeemable preferred stocks | 1,417.6 |  |  | 0 |  |  | 0 |  |  | (163.2) |  |  | 1,254.4 |  |  | 2.4 |
Common equities | 803.7 |  |  | 0 |  |  | 0 |  |  | 1,861.6 |  |  | 2,665.3 |  |  | 5.1 |
Total equity securities | 2,221.3 |  |  | 0 |  |  | 0 |  |  | 1,698.4 |  |  | 3,919.7 |  |  | 7.5 |
Total portfolio 1 | $ | 54,664.6 |  |  | $ | 1.8 |  |  | $ | (3,943.1) |  |  | $ | 1,607.1 |  |  | $ | 52,330.4 |  |  | 100.0 | %
($ in millions) | Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Net Holding Period Gains (Losses) |  | Fair Value |  | % of Total Fair Value
December 31, 2022 |  |  |  |  |  |  |  |  |  |  |
Available-for-sale securities: |  |  |  |  |  |  |  |  |  |  |
Fixed maturities: |  |  |  |  |  |  |  |  |  |  |
U.S. government obligations | $ | 26,770.7 |  |  | $ | 1.4 |  |  | $ | (1,604.7) |  |  | $ | 0 |  |  | $ | 25,167.4 |  |  | 47.0 | %
State and local government obligations | 2,180.0 |  |  | 0 |  |  | (202.9) |  |  | 0 |  |  | 1,977.1 |  |  | 3.7 |
Foreign government obligations | 16.8 |  |  | 0 |  |  | (1.3) |  |  | 0 |  |  | 15.5 |  |  | 0.1 |
Corporate debt securities | 10,125.8 |  |  | 9.8 |  |  | (676.1) |  |  | (46.8) |  |  | 9,412.7 |  |  | 17.6 |
Residential mortgage-backed securities | 696.1 |  |  | 0.3 |  |  | (17.5) |  |  | (12.1) |  |  | 666.8 |  |  | 1.2 |
Commercial mortgage-backed securities | 5,446.0 |  |  | 1.5 |  |  | (784.0) |  |  | 0 |  |  | 4,663.5 |  |  | 8.7 |
Other asset-backed securities | 4,826.0 |  |  | 0.9 |  |  | (260.5) |  |  | (1.8) |  |  | 4,564.6 |  |  | 8.5 |
Redeemable preferred stocks | 202.6 |  |  | 0 |  |  | (4.5) |  |  | (13.8) |  |  | 184.3 |  |  | 0.3 |
Total fixed maturities | 50,264.0 |  |  | 13.9 |  |  | (3,551.5) |  |  | (74.5) |  |  | 46,651.9 |  |  | 87.1 |
Short-term investments | 2,861.7 |  |  | 0 |  |  | 0 |  |  | 0 |  |  | 2,861.7 |  |  | 5.4 |
Total available-for-sale securities | 53,125.7 |  |  | 13.9 |  |  | (3,551.5) |  |  | (74.5) |  |  | 49,513.6 |  |  | 92.5 |
Equity securities: |  |  |  |  |  |  |  |  |  |  |
Nonredeemable preferred stocks | 1,364.2 |  |  | 0 |  |  | 0 |  |  | (151.0) |  |  | 1,213.2 |  |  | 2.3 |
Common equities | 826.1 |  |  | 0 |  |  | 0 |  |  | 1,995.4 |  |  | 2,821.5 |  |  | 5.2 |
Total equity securities | 2,190.3 |  |  | 0 |  |  | 0 |  |  | 1,844.4 |  |  | 4,034.7 |  |  | 7.5 |
Total portfolio 1 | $ | 55,316.0 |  |  | $ | 13.9 |  |  | $ | (3,551.5) |  |  | $ | 1,769.9 |  |  | $ | 53,548.3 |  |  | 100.0 | %
1 At September 30, 2023 and 2022, we had $167.3 million and $74.7 million, respectively, of net unsettled security purchase transactions included in other liabilities, compared to $34.4 million included in other assets at December 31, 2022. The total fair value of the portfolio at September 30, 2023 and 2022, and December 31, 2022, included $4.1 billion, $4.2 billion, and $4.4 billion, respectively, of securities held in a consolidated, non-insurance subsidiary of the holding company, net of unsettled security transactions.
Hybrid Instruments Table | Certain securities in our fixed-maturity portfolio are accounted for as hybrid securities because they contain embedded derivatives that are not deemed to be clearly and closely related to the host investments. These securities are reported at fair value:
| September 30, |  |
(millions) | 2023 |  | 2022 |  | Dec. 31, 2022
Fixed Maturities: |  |  |  |  |
Corporate debt securities | $ | 511.1 |  |  | $ | 500.4 |  |  | $ | 535.4 |
Residential mortgage-backed securities | 410.8 |  |  | 550.8 |  |  | 509.6 |
Other asset-backed securities | 19.4 |  |  | 51.4 |  |  | 42.0 |
Redeemable preferred stocks | 136.4 |  |  | 133.0 |  |  | 134.7 |
Total hybrid securities | $ | 1,077.7 |  |  | $ | 1,235.6 |  |  | $ | 1,221.7 |
Investments Classified by Contractual Maturity Date | The composition of fixed maturities by maturity at September 30, 2023, was:
(millions) | Cost |  | Fair Value
Less than one year | $ | 9,639.9 |  |  | $ | 9,387.8 |
One to five years | 37,572.4 |  |  | 35,419.0 |
Five to ten years | 13,197.7 |  |  | 11,710.3 |
Ten years or greater | 80.6 |  |  | 74.8 |
Total | $ | 60,490.6 |  |  | $ | 56,591.9 |
Schedule of Unrealized Loss on Investments | The following tables show the composition of gross unrealized losses by major security type and by the length of time that individual securities have been in a continuous unrealized loss position:
| Total No. of Sec. | Total Fair Value | Gross Unrealized Losses | Less than 12 Months |  |  | 12 Months or Greater
($ in millions) | No. of Sec. | Fair Value | Unrealized Losses |  |  | No. of Sec. | Fair Value | Unrealized Losses
September 30, 2023 |  |  |  |  |  |  |  |  |  |  |
U.S. government obligations | 173 |  | $ | 34,293.8 |  | $ | (2,098.4) |  | 37 |  | $ | 16,686.2 |  | $ | (557.6) |  |  |  | 136 |  | $ | 17,607.6 |  | $ | (1,540.8) |
State and local government obligations | 356 |  | 2,033.9 |  | (203.3) |  | 46 |  | 359.6 |  | (7.6) |  |  |  | 310 |  | 1,674.3 |  | (195.7) |
Foreign government obligations | 1 |  | 15.4 |  | (1.5) |  | 0 |  | 0 |  | 0 |  |  |  | 1 |  | 15.4 |  | (1.5) |
Corporate debt securities | 467 |  | 9,490.0 |  | (591.8) |  | 164 |  | 3,380.4 |  | (94.1) |  |  |  | 303 |  | 6,109.6 |  | (497.7) |
Residential mortgage-backed securities | 40 |  | 99.9 |  | (13.0) |  | 2 |  | 0.4 |  | 0 |  |  |  | 38 |  | 99.5 |  | (13.0) |
Commercial mortgage-backed securities | 196 |  | 3,960.8 |  | (723.9) |  | 0 |  | 0 |  | 0 |  |  |  | 196 |  | 3,960.8 |  | (723.9) |
Other asset-backed securities | 295 |  | 5,001.8 |  | (210.1) |  | 104 |  | 2,056.9 |  | (8.8) |  |  |  | 191 |  | 2,944.9 |  | (201.3) |
Redeemable preferred stocks | 3 |  | 30.6 |  | (4.3) |  | 0 |  | 0 |  | 0 |  |  |  | 3 |  | 30.6 |  | (4.3) |
Total fixed maturities | 1,531 |  | $ | 54,926.2 |  | $ | (3,846.3) |  | 353 |  | $ | 22,483.5 |  | $ | (668.1) |  |  |  | 1,178 |  | $ | 32,442.7 |  | $ | (3,178.2) |
| Total No. of Sec. | Total Fair Value | Gross Unrealized Losses | Less than 12 Months |  | 12 Months or Greater
($ in millions) | No. of Sec. | Fair Value | Unrealized Losses |  | No. of Sec. | Fair Value | Unrealized Losses
September 30, 2022 |  |  |  |  |  |  |  |  |  |
U.S. government obligations | 157 |  | $ | 22,385.4 |  | $ | (1,855.4) |  | 103 |  | $ | 16,085.8 |  | $ | (1,095.6) |  |  | 54 |  | $ | 6,299.6 |  | $ | (759.8) |
State and local government obligations | 353 |  | 1,911.0 |  | (215.4) |  | 292 |  | 1,363.1 |  | (129.8) |  |  | 61 |  | 547.9 |  | (85.6) |
Foreign government obligations | 1 |  | 15.3 |  | (1.4) |  | 1 |  | 15.3 |  | (1.4) |  |  | 0 |  | 0 |  | 0 |
Corporate debt securities | 452 |  | 8,885.6 |  | (832.5) |  | 391 |  | 7,875.5 |  | (699.0) |  |  | 61 |  | 1,010.1 |  | (133.5) |
Residential mortgage-backed securities | 44 |  | 165.1 |  | (16.5) |  | 34 |  | 126.0 |  | (11.8) |  |  | 10 |  | 39.1 |  | (4.7) |
Commercial mortgage-backed securities | 234 |  | 5,074.3 |  | (747.4) |  | 182 |  | 3,856.0 |  | (425.4) |  |  | 52 |  | 1,218.3 |  | (322.0) |
Other asset-backed securities | 277 |  | 4,544.8 |  | (268.9) |  | 217 |  | 3,597.1 |  | (183.4) |  |  | 60 |  | 947.7 |  | (85.5) |
Redeemable preferred stocks | 4 |  | 48.6 |  | (5.6) |  | 3 |  | 37.7 |  | (4.0) |  |  | 1 |  | 10.9 |  | (1.6) |
Total fixed maturities | 1,522 |  | $ | 43,030.1 |  | $ | (3,943.1) |  | 1,223 |  | $ | 32,956.5 |  | $ | (2,550.4) |  |  | 299 |  | $ | 10,073.6 |  | $ | (1,392.7) |
| Total No. of Sec. | Total Fair Value | Gross Unrealized Losses | Less than 12 Months |  | 12 Months or Greater
($ in millions) | No. of Sec. | Fair Value | Unrealized Losses |  | No. of Sec. | Fair Value | Unrealized Losses
December 31, 2022 |  |  |  |  |  |  |  |  |  |
U.S. government obligations | 160 |  | $ | 24,802.5 |  | $ | (1,604.7) |  | 90 |  | $ | 17,327.2 |  | $ | (699.2) |  |  | 70 |  | $ | 7,475.3 |  | $ | (905.5) |
State and local government obligations | 348 |  | 1,948.8 |  | (202.9) |  | 239 |  | 1,124.2 |  | (76.8) |  |  | 109 |  | 824.6 |  | (126.1) |
Foreign government obligations | 1 |  | 15.5 |  | (1.3) |  | 0 |  | 0 |  | 0 |  |  | 1 |  | 15.5 |  | (1.3) |
Corporate debt securities | 422 |  | 8,449.6 |  | (676.1) |  | 285 |  | 5,717.6 |  | (426.1) |  |  | 137 |  | 2,732.0 |  | (250.0) |
Residential mortgage-backed securities | 45 |  | 151.0 |  | (17.5) |  | 27 |  | 65.1 |  | (6.8) |  |  | 18 |  | 85.9 |  | (10.7) |
Commercial mortgage-backed securities | 226 |  | 4,651.1 |  | (784.0) |  | 99 |  | 1,702.0 |  | (192.1) |  |  | 127 |  | 2,949.1 |  | (591.9) |
Other asset-backed securities | 262 |  | 4,247.8 |  | (260.5) |  | 130 |  | 2,144.8 |  | (100.9) |  |  | 132 |  | 2,103.0 |  | (159.6) |
Redeemable preferred stocks | 4 |  | 49.6 |  | (4.5) |  | 3 |  | 38.5 |  | (3.1) |  |  | 1 |  | 11.1 |  | (1.4) |
Total fixed maturities | 1,468 |  | $ | 44,315.9 |  | $ | (3,551.5) |  | 873 |  | $ | 28,119.4 |  | $ | (1,505.0) |  |  | 595 |  | $ | 16,196.5 |  | $ | (2,046.5) |
Realized Gain (Loss) on Investments | The components of net realized gains (losses) for the three and nine months ended September 30, were:
| Three Months |  | Nine Months
(millions) | 2023 |  | 2022 |  | 2023 |  | 2022
Gross realized gains on security sales |  |  |  |  |  |  |
Available-for-sale securities: |  |  |  |  |  |  |
U.S. government obligations | $ | 0.2 |  |  | $ | 0 |  |  | $ | 4.2 |  |  | $ | 4.6 |
Corporate debt securities | 0.7 |  |  | 0.3 |  |  | 0.8 |  |  | 6.8 |
Residential mortgage-backed securities | 0 |  |  | 0 |  |  | 0 |  |  | 0.7 |
Other asset-backed securities | 0 |  |  | 0 |  |  | 0 |  |  | 0.1 |
Total available-for-sale securities | 0.9 |  |  | 0.3 |  |  | 5.0 |  |  | 12.2 |
Equity securities: |  |  |  |  |  |  |
Nonredeemable preferred stocks | 0 |  |  | 0.1 |  |  | 0.3 |  |  | 17.6 |
Common equities | 0.3 |  |  | 1.4 |  |  | 354.2 |  |  | 832.5 |
Total equity securities | 0.3 |  |  | 1.5 |  |  | 354.5 |  |  | 850.1 |
Subtotal gross realized gains on security sales | 1.2 |  |  | 1.8 |  |  | 359.5 |  |  | 862.3 |
Gross realized losses on security sales |  |  |  |  |  |  |
Available-for-sale securities: |  |  |  |  |  |  |
U.S. government obligations | (14.6) |  |  | 0 |  |  | (27.2) |  |  | (233.5) |
State and local government obligations | 0 |  |  | 0 |  |  | 0 |  |  | (1.0) |
Corporate debt securities | (19.1) |  |  | (14.0) |  |  | (69.3) |  |  | (51.8) |
Commercial mortgage-backed securities | (20.6) |  |  | (44.8) |  |  | (100.6) |  |  | (58.6) |
Other asset-backed securities | (5.2) |  |  | 0 |  |  | (5.6) |  |  | (2.1) |
Short-term investments | 0 |  |  | 0 |  |  | (0.4) |  |  | (0.3) |
Total available-for-sale securities | (59.5) |  |  | (58.8) |  |  | (203.1) |  |  | (347.3) |
Equity securities: |  |  |  |  |  |  |
Nonredeemable preferred stocks | (7.4) |  |  | (5.1) |  |  | (117.6) |  |  | (7.0) |
Common equities | (8.9) |  |  | 0 |  |  | (21.8) |  |  | (78.0) |
Total equity securities | (16.3) |  |  | (5.1) |  |  | (139.4) |  |  | (85.0) |
Subtotal gross realized losses on security sales | (75.8) |  |  | (63.9) |  |  | (342.5) |  |  | (432.3) |
Net realized gains (losses) on security sales |  |  |  |  |  |  |
Available-for-sale securities: |  |  |  |  |  |  |
U.S. government obligations | (14.4) |  |  | 0 |  |  | (23.0) |  |  | (228.9) |
State and local government obligations | 0 |  |  | 0 |  |  | 0 |  |  | (1.0) |
Corporate debt securities | (18.4) |  |  | (13.7) |  |  | (68.5) |  |  | (45.0) |
Residential mortgage-backed securities | 0 |  |  | 0 |  |  | 0 |  |  | 0.7 |
Commercial mortgage-backed securities | (20.6) |  |  | (44.8) |  |  | (100.6) |  |  | (58.6) |
Other asset-backed securities | (5.2) |  |  | 0 |  |  | (5.6) |  |  | (2.0) |
Short-term investments | 0 |  |  | 0 |  |  | (0.4) |  |  | (0.3) |
Total available-for-sale securities | (58.6) |  |  | (58.5) |  |  | (198.1) |  |  | (335.1) |
Equity securities: |  |  |  |  |  |  |
Nonredeemable preferred stocks | (7.4) |  |  | (5.0) |  |  | (117.3) |  |  | 10.6 |
Common equities | (8.6) |  |  | 1.4 |  |  | 332.4 |  |  | 754.5 |
Total equity securities | (16.0) |  |  | (3.6) |  |  | 215.1 |  |  | 765.1 |
Subtotal net realized gains (losses) on security sales | (74.6) |  |  | (62.1) |  |  | 17.0 |  |  | 430.0 |
Other assets |  |  |  |  |  |  |
Gain | 8.4 |  |  | 0 |  |  | 21.6 |  |  | 0 |
Impairment | (2.3) |  |  | (2.2) |  |  | (6.8) |  |  | (6.5) |
Subtotal net realized gains (losses) on other assets | 6.1 |  |  | (2.2) |  |  | 14.8 |  |  | (6.5) |
Net holding period gains (losses) |  |  |  |  |  |  |
Hybrid securities | (0.3) |  |  | (11.4) |  |  | 18.4 |  |  | (98.8) |
Equity securities | (80.2) |  |  | (140.7) |  |  | (0.5) |  |  | (2,164.1) |
Subtotal net holding period gains (losses) | (80.5) |  |  | (152.1) |  |  | 17.9 |  |  | (2,262.9) |
Total net realized gains (losses) on securities | $ | (149.0) |  |  | $ | (216.4) |  |  | $ | 49.7 |  |  | $ | (1,839.4) |
Components of Equity Realized Gains (Losses) | The following table reflects our holding period realized gains (losses) recognized on equity securities held at the respective periods ended September 30:
| Three Months |  | Nine Months
(millions) | 2023 | 2022 |  | 2023 | 2022
Total net gains (losses) recognized during the period on equity securities | $ | (96.2) |  | $ | (144.3) |  |  | $ | 214.6 |  | $ | (1,399.0) |
Less: Net gains (losses) recognized on equity securities sold during the period | (16.0) |  | (3.6) |  |  | 215.1 |  | 765.1 |
Net holding period gains (losses) recognized during the period on equity securities held at period end | $ | (80.2) |  | $ | (140.7) |  |  | $ | (0.5) |  | $ | (2,164.1) |
Components of Net Investment Income | The components of net investment income for the three and nine months ended September 30, were:
| Three Months |  | Nine Months
(millions) | 2023 | 2022 |  | 2023 | 2022
Available-for-sale securities: |  |  |  |  |
Fixed maturities: |  |  |  |  |
U.S. government obligations | $ | 237.0 |  | $ | 86.1 |  |  | $ | 591.7 |  | $ | 205.4 |
State and local government obligations | 12.3 |  | 9.8 |  |  | 34.5 |  | 29.3 |
Foreign government obligations | 0.1 |  | 0.1 |  |  | 0.2 |  | 0.2 |
Corporate debt securities | 94.8 |  | 71.8 |  |  | 261.9 |  | 215.4 |
Residential mortgage-backed securities | 7.6 |  | 8.8 |  |  | 22.6 |  | 23.2 |
Commercial mortgage-backed securities | 48.7 |  | 48.3 |  |  | 147.9 |  | 138.1 |
Other asset-backed securities | 62.9 |  | 52.1 |  |  | 173.0 |  | 116.5 |
Redeemable preferred stocks | 2.6 |  | 3.0 |  |  | 8.2 |  | 8.5 |
Total fixed maturities | 466.0 |  | 280.0 |  |  | 1,240.0 |  | 736.6 |
Short-term investments | 21.6 |  | 24.8 |  |  | 71.1 |  | 29.6 |
Total available-for-sale securities | 487.6 |  | 304.8 |  |  | 1,311.1 |  | 766.2 |
Equity securities: |  |  |  |  |
Nonredeemable preferred stocks | 11.9 |  | 17.3 |  |  | 40.3 |  | 53.6 |
Common equities | 10.7 |  | 11.5 |  |  | 32.9 |  | 48.4 |
Total equity securities | 22.6 |  | 28.8 |  |  | 73.2 |  | 102.0 |
Investment income | 510.2 |  | 333.6 |  |  | 1,384.3 |  | 868.2 |
Investment expenses | (7.2) |  | (5.8) |  |  | (18.8) |  | (17.4) |
Net investment income | $ | 503.0 |  | $ | 327.8 |  |  | $ | 1,365.5 |  | $ | 850.8 |

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