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Equity (Tables) | 12 Months Ended
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Dec. 31, 2020
Equity [Abstract] |
Summary of common stock | The following table describes the number of shares authorized, issued and outstanding of our common stock as of December 31, 2020, 2019 and 2018:
| As of December 31, 2020 |  | As of December 31, 2019 |  | As of December 31, 2018
(In millions) | Authorized |  | Issued |  | Outstanding |  | Authorized |  | Issued |  | Outstanding |  | Authorized |  | Issued |  | Outstanding
Common stock | 1,000.0 |  |  | 176.2 |  |  | 152.4 |  |  | 1,000.0 |  |  | 198.0 |  |  | 174.2 |  |  | 1,000.0 |  |  | 221.0 |  |  | 197.2 |
Schedule of Accumulated Other Comprehensive Income (Loss) | The following tables summarize the changes in accumulated other comprehensive income (loss), net of tax by component:
|  | December 31, 2020
(In millions) |  | Unrealized Gains (Losses) on Securities Available for Sale, net of tax |  | Unrealized Gains (Losses) on Cash Flow Hedges, net of tax |  | Gains (Losses) on Net Investment Hedge, Net of Tax |  | Unfunded Status of Postretirement Benefit Plans, net of tax |  | Currency Translation Adjustments |  | Total
Balance, December 31, 2019 |  | $ | 4.2 |  |  | $ | 7.8 |  |  | $ | 25.1 |  |  | $ | (32.8) |  |  | $ | (139.5) |  |  | $ | (135.2) |
Other comprehensive income (loss) before reclassifications |  | (9.3) |  |  | (165.0) |  |  | (30.7) |  |  | (33.5) |  |  | 92.9 |  |  | (145.6) |
Amounts reclassified from accumulated other comprehensive income (loss) |  | 6.5 |  |  | (21.8) |  |  | (2.9) |  |  | — |  |  | — |  |  | (18.2) |
Net current period other comprehensive income (loss) |  | (2.8) |  |  | (186.8) |  |  | (33.6) |  |  | (33.5) |  |  | 92.9 |  |  | (163.8) |
Balance, December 31, 2020 |  | $ | 1.4 |  |  | $ | (179.0) |  |  | $ | (8.5) |  |  | $ | (66.3) |  |  | $ | (46.6) |  |  | $ | (299.0) |
|  | December 31, 2019
(In millions) |  | Unrealized Gains (Losses) on Securities Available for Sale, net of tax |  | Unrealized Gains (Losses) on Cash Flow Hedges, net of tax |  | Gains (Losses) on Net Investment Hedge, Net of Tax |  | Unfunded Status of Postretirement Benefit Plans, net of tax |  | Currency Translation Adjustments |  | Total
Balance, December 31, 2018 |  | $ | (4.0) |  |  | $ | 34.7 |  |  | $ | 3.5 |  |  | $ | (31.3) |  |  | $ | (243.3) |  |  | $ | (240.4) |
Other comprehensive income (loss) before reclassifications |  | 11.8 |  |  | 88.1 |  |  | 28.6 |  |  | (1.5) |  |  | 103.8 |  |  | 230.8 |
Amounts reclassified from accumulated other comprehensive income (loss) |  | (3.6) |  |  | (115.0) |  |  | (7.0) |  |  | — |  |  | — |  |  | (125.6) |
Net current period other comprehensive income (loss) |  | 8.2 |  |  | (26.9) |  |  | 21.6 |  |  | (1.5) |  |  | 103.8 |  |  | 105.2 |
Balance, December 31, 2019 |  | $ | 4.2 |  |  | $ | 7.8 |  |  | $ | 25.1 |  |  | $ | (32.8) |  |  | $ | (139.5) |  |  | $ | (135.2) |
|  | December 31, 2018
(In millions) |  | Unrealized Gains (Losses) on Securities Available for Sale, net of tax |  | Unrealized Gains (Losses) on Cash Flow Hedges, net of tax |  | Gains (Losses) on Net Investment Hedge, Net of Tax |  | Unfunded Status of Postretirement Benefit Plans, net of tax |  | Currency Translation Adjustments |  | Total
Balance, December 31, 2017 |  | $ | (1.6) |  |  | $ | (104.5) |  |  | $ | — |  |  | $ | (36.8) |  |  | $ | (175.5) |  |  | $ | (318.4) |
Amount reclassified, net of tax, upon adoption of ASU 2016-01 |  | 1.5 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 1.5 |
Balance, January 1, 2018 |  | (0.1) |  |  | (104.5) |  |  | — |  |  | (36.8) |  |  | (175.5) |  |  | (316.9) |
Other comprehensive income (loss) before reclassifications |  | (10.6) |  |  | 97.4 |  |  | 5.0 |  |  | 5.5 |  |  | (67.8) |  |  | 29.5 |
Amounts reclassified from accumulated other comprehensive income (loss) |  | 6.7 |  |  | 41.8 |  |  | (1.5) |  |  | — |  |  | — |  |  | 47.0 |
Net current period other comprehensive income (loss) |  | (3.9) |  |  | 139.2 |  |  | 3.5 |  |  | 5.5 |  |  | (67.8) |  |  | 76.5 |
Balance, December 31, 2018 |  | $ | (4.0) |  |  | $ | 34.7 |  |  | $ | 3.5 |  |  | $ | (31.3) |  |  | $ | (243.3) |  |  | $ | (240.4) |
Reclassification out of Accumulated Other Comprehensive Income | The following table summarizes the amounts reclassified from accumulated other comprehensive income:
(In millions) |  | Income Statement Location |  | Amounts Reclassified from Accumulated Other Comprehensive Income
| For the Years Ended December 31,
| 2020 |  | 2019 |  | 2018
Gains (losses) on securities available for sale |  | Other income (expense) |  | $ | (8.2) |  |  | $ | 4.5 |  |  | $ | (8.5) |
|  | Income tax benefit (expense) |  | 1.7 |  |  | (0.9) |  |  | 1.8 |
Gains (losses) on cash flow hedges |  | Revenues |  | 18.3 |  |  | 118.6 |  |  | (42.5) |
|  | Operating expenses |  | 3.3 |  |  | (3.3) |  |  | 0.2 |
|  | Other income (expense) |  | 0.3 |  |  | 0.3 |  |  | 0.3 |
|  | Income tax benefit (expense) |  | (0.1) |  |  | (0.6) |  |  | 0.2 |
Gains (losses) on net investment hedge |  | Other Income (expense) |  | 2.9 |  |  | 7.0 |  |  | 1.5 |
Total reclassifications, net of tax |  |  |  | $ | 18.2 |  |  | $ | 125.6 |  |  | $ | (47.0) |

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