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Stockholders' Equity - Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Other Comprehensive Income (Loss) |  |  |  |
Other comprehensive income (loss), pre-tax | $ 1,079.8 | $ 2,602.6 | $ (719.3) | $ 581.5
Other comprehensive income (loss), tax | (230.0) | (554.5) | 139.6 | (179.7)
Other comprehensive income (loss) | 849.8 | 2,048.1 | (579.7) | 401.8
Net unrealized gains (losses) on available-for-sale securities including NCI |  |  |  |
Other Comprehensive Income (Loss) |  |  |  |
Other comprehensive income (loss) before reclassifications, pre-tax | 1,361.5 | 4,195.7 | (1,915.2) | 1,418.0
Adjustments for assumed changes in amortization patterns, pre-tax | (55.5) | (336.4) | 89.1 | (3.9)
Adjustments for assumed changes in policyholder liabilities, pre-tax | (318.8) | (1,232.5) | 1,096.5 | (570.3)
Other comprehensive income (loss), pre-tax | 1,013.4 | 2,578.9 | (730.8) | 786.4
Other comprehensive income (loss) before reclassifications, tax | (273.0) | (900.4) | 427.5 | (300.1)
Reclassification from accumulated other comprehensive income, tax | (5.7) | 11.0 |  | 13.6
Adjustments for assumed changes in amortization patterns, tax | 11.7 | 70.6 | (18.7) | 0.8
Adjustments for assumed changes in policyholder liabilities, tax | 44.5 | 277.6 | (260.5) | 125.4
Other comprehensive income (loss), tax | (222.5) | (541.2) | 148.3 | (160.3)
Other comprehensive income (loss) before reclassifications, after-tax | 1,088.5 | 3,295.3 | (1,487.7) | 1,117.9
Reclassification from accumulated other comprehensive income, after-tax | 20.5 | (36.9) | (1.2) | (43.8)
Adjustments for assumed changes in amortization patterns, after-tax | (43.8) | (265.8) | 70.4 | (3.1)
Adjustments for assumed changes in policyholder liabilities, after-tax | (274.3) | (954.9) | 836.0 | (444.9)
Other comprehensive income (loss) | 790.9 | 2,037.7 | (582.5) | 626.1
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 | 26.2 | (47.9) | (1.2) | (57.4)
Net unrealized gains (losses) on derivative instruments including NCI |  |  |  |
Other Comprehensive Income (Loss) |  |  |  |
Other comprehensive income (loss) before reclassifications, pre-tax | 21.8 | (10.8) | 22.5 | 55.4
Reclassification from accumulated other comprehensive income, pre-tax | (4.7) | (12.6) | (9.1) | (18.2)
Adjustments for assumed changes in amortization patterns, pre-tax |  | 1.0 |  | 0.7
Adjustments for assumed changes in policyholder liabilities, pre-tax | 0.4 | 1.7 | 1.4 | 2.9
Other comprehensive income (loss), pre-tax | 17.5 | (20.7) | 14.8 | 40.8
Other comprehensive income (loss) before reclassifications, tax | (4.6) | 3.1 | (4.7) | (11.1)
Reclassification from accumulated other comprehensive income, tax | 1.0 | 1.8 | 1.9 | 3.3
Adjustments for assumed changes in amortization patterns, tax |  | (0.2) |  | (0.2)
Adjustments for assumed changes in policyholder liabilities, tax |  | (0.4) | (0.3) | (0.6)
Other comprehensive income (loss), tax | (3.6) | 4.3 | (3.1) | (8.6)
Other comprehensive income (loss) before reclassifications, after-tax | 17.2 | (7.7) | 17.8 | 44.3
Reclassification from accumulated other comprehensive income, after-tax | (3.7) | (10.8) | (7.2) | (14.9)
Adjustments for assumed changes in amortization patterns, after-tax |  | 0.8 |  | 0.5
Adjustments for assumed changes in policyholder liabilities, after-tax | 0.4 | 1.3 | 1.1 | 2.3
Other comprehensive income (loss) | 13.9 | (16.4) | 11.7 | 32.2
Foreign currency translation adjustment including NCI |  |  |  |
Other Comprehensive Income (Loss) |  |  |  |
Other comprehensive income (loss) before reclassifications, pre-tax |  | 30.0 |  | (306.6)
Other comprehensive income (loss), pre-tax | 35.9 | 30.0 | (20.2) | (275.1)
Other comprehensive income (loss) before reclassifications, tax |  | (13.6) |  | (2.8)
Other comprehensive income (loss), tax | (0.5) | (13.6) | (0.6) | (2.8)
Other comprehensive income (loss) before reclassifications, after-tax |  | 16.4 |  | (309.4)
Reclassification from accumulated other comprehensive income, after-tax |  |  |  | 31.5
Other comprehensive income (loss) | 35.4 | 16.4 | (20.8) | (277.9)
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 | 13.0 | 14.4 | 16.9 | 29.4
Other comprehensive income (loss) before reclassifications, tax |  | (0.1) | 1.9 | (0.2)
Reclassification from accumulated other comprehensive income, tax | (3.4) | (3.9) | (6.9) | (7.8)
Other comprehensive income (loss), tax | (3.4) | (4.0) | (5.0) | (8.0)
Other comprehensive income (loss) before reclassifications, after-tax |  | (0.1) | (7.2) | 0.4
Reclassification from accumulated other comprehensive income, after-tax | 9.6 | 10.5 | 19.1 | 21.0
Other comprehensive income (loss) | 9.6 | 10.4 | 11.9 | 21.4
Unrecognized postretirement benefit obligation including NCI | Operating expense |  |  |  |
Other Comprehensive Income (Loss) |  |  |  |
Reclassification from accumulated other comprehensive income, pre-tax | $ 13.0 | $ 14.4 | $ 26.0 | $ 28.8

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Data Type: | na
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