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Stockholders' Equity - Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Other Comprehensive Income (Loss) |  |
Other comprehensive income (loss), pre-tax | $ (1,799.1) | $ (2,021.1)
Other comprehensive income (loss), tax | 369.6 | 374.8
Other comprehensive income (loss) | (1,429.5) | (1,646.3)
Net unrealized gains (losses) on available-for-sale securities including NCI |  |
Other Comprehensive Income (Loss) |  |
Other comprehensive income (loss) before reclassifications, pre-tax | (3,276.7) | (2,777.7)
Adjustments for assumed changes in amortization patterns, pre-tax | 144.6 | 332.5
Adjustments for assumed changes in policyholder liabilities, pre-tax | 1,415.3 | 662.2
Other comprehensive income (loss), pre-tax | (1,744.2) | (1,792.5)
Other comprehensive income (loss) before reclassifications, tax | 700.5 | 600.3
Reclassification from accumulated other comprehensive income, tax | 5.7 | 2.6
Adjustments for assumed changes in amortization patterns, tax | (30.4) | (69.8)
Adjustments for assumed changes in policyholder liabilities, tax | (305.0) | (152.2)
Other comprehensive income (loss), tax | 370.8 | 380.9
Other comprehensive income (loss) before reclassifications, after-tax | (2,576.2) | (2,177.4)
Reclassification from accumulated other comprehensive income, after-tax | (21.7) | (6.9)
Adjustments for assumed changes in amortization patterns, after-tax | 114.2 | 262.7
Adjustments for assumed changes in policyholder liabilities, after-tax | 1,110.3 | 510.0
Other comprehensive income (loss) | (1,373.4) | (1,411.6)
Net unrealized gains (losses) on available-for-sale securities including NCI | Net realized capital gains (losses) |  |
Other Comprehensive Income (Loss) |  |
Reclassification from accumulated other comprehensive income, pre-tax | (27.4) | (9.5)
Net unrealized gains (losses) on derivative instruments including NCI |  |
Other Comprehensive Income (Loss) |  |
Other comprehensive income (loss) before reclassifications, pre-tax | 0.7 | 66.2
Reclassification from accumulated other comprehensive income, pre-tax | (4.4) | (5.6)
Adjustments for assumed changes in amortization patterns, pre-tax |  | (0.3)
Adjustments for assumed changes in policyholder liabilities, pre-tax | 1.0 | 1.2
Other comprehensive income (loss), pre-tax | (2.7) | 61.5
Other comprehensive income (loss) before reclassifications, tax | (0.1) | (14.2)
Reclassification from accumulated other comprehensive income, tax | 0.9 | 1.5
Adjustments for assumed changes in policyholder liabilities, tax | (0.3) | (0.2)
Other comprehensive income (loss), tax | 0.5 | (12.9)
Other comprehensive income (loss) before reclassifications, after-tax | 0.6 | 52.0
Reclassification from accumulated other comprehensive income, after-tax | (3.5) | (4.1)
Adjustments for assumed changes in amortization patterns, after-tax |  | (0.3)
Adjustments for assumed changes in policyholder liabilities, after-tax | 0.7 | 1.0
Other comprehensive income (loss) | (2.2) | 48.6
Foreign currency translation adjustment including NCI |  |
Other Comprehensive Income (Loss) |  |
Other comprehensive income (loss) before reclassifications, pre-tax |  | (336.6)
Other comprehensive income (loss), pre-tax | (56.1) | (305.1)
Other comprehensive income (loss) before reclassifications, tax |  | 10.8
Other comprehensive income (loss), tax | (0.1) | 10.8
Other comprehensive income (loss) before reclassifications, after-tax |  | (325.8)
Reclassification from accumulated other comprehensive income, after-tax |  | 31.5
Other comprehensive income (loss) | (56.2) | (294.3)
Foreign currency translation adjustment including NCI | Net realized capital gains (losses) |  |
Other Comprehensive Income (Loss) |  |
Reclassification from accumulated other comprehensive income, pre-tax |  | 31.5
Unrecognized postretirement benefit obligation including NCI |  |
Other Comprehensive Income (Loss) |  |
Other comprehensive income (loss) before reclassifications, pre-tax | (9.1) | 0.6
Other comprehensive income (loss), pre-tax | 3.9 | 15.0
Other comprehensive income (loss) before reclassifications, tax | 1.9 | (0.1)
Reclassification from accumulated other comprehensive income, tax | (3.5) | (3.9)
Other comprehensive income (loss), tax | (1.6) | (4.0)
Other comprehensive income (loss) before reclassifications, after-tax | (7.2) | 0.5
Reclassification from accumulated other comprehensive income, after-tax | 9.5 | 10.5
Other comprehensive income (loss) | 2.3 | 11.0
Unrecognized postretirement benefit obligation including NCI | Operating expense |  |
Other Comprehensive Income (Loss) |  |
Reclassification from accumulated other comprehensive income, pre-tax | $ 13.0 | $ 14.4

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