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Capital Structure - Common Stock (Details) - USD ($) |  | 1 Months Ended | 2 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jan. 21, 2021 | Mar. 31, 2019 | Feb. 27, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Quarterly dividends per share (usd per share) |  |  |  |  |  |  | $ 0.30 | $ 0.03 | $ 0.03
Dividends paid per share (in usd per share) |  |  |  |  |  |  | $ 1.20 | 0.12 | $ 0.12
Common stock, dividends, proposed annual amount, per share (usd per share) |  |  |  | $ 1.20 |  |  |  | $ 0.12 |
Long-term capital allocation policy, target allocation of cash generated allocated to growth investments, percentage |  |  |  |  | 50.00% |  |  |  |
Long-term capital allocation, target allocation, cash generated allocated returned to shareholders, percentage |  |  |  |  | 50.00% |  |  |  |
Eligible compensation withholding, minimum, percentage |  | 1.00% |  |  |  |  |  |  |
Eligible compensation withholding, maximum, percentage |  | 10.00% |  |  |  |  | 10.00% |  |
Market value on offering date percentage |  |  |  |  |  | 95.00% |  |  |
Exercise price as a percentage of fair value (as a percent) |  | 95.00% |  |  |  |  | 85.00% |  |
Treasury stock reserved for issuance under the ESPP (in shares) |  |  |  |  |  |  | 2,753,591 |  |
Shares repurchased (in shares) |  |  |  |  |  |  | 6,062,783 | 36,301,882 | 35,234,664
Capital Allocation Plan |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Stock repurchase program, authorized amount |  |  |  |  | $ 1,250,000,000 |  |  | $ 1,250,000,000 | $ 1,500,000,000
Shares repurchased (in shares) |  |  |  |  |  |  | 6,774,031 | 37,238,810 | 35,234,664
2018 Capital Allocation Plan |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Shares repurchased (in shares) |  |  |  |  |  | 250,000,000 |  |  | 1,250,000,000
2019 Capital Allocation Plan |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Shares repurchased (in shares) |  |  | 56,000,000 |  |  |  |  | 1,194,000,000 |
Subsequent Event |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Dividends per common share (in usd per share) | $ 0.325 |  |  |  |  |  |  |  |
Scenario, Plan | Subsequent Event |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Common stock, dividends, proposed annual amount, per share (usd per share) | $ 1.30 |  |  |  |  |  |  |  |
Common stock, annual dividends increase, percentage | 8.00% |  |  |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Annual dividend growth rate, percentage |  |  |  |  | 700.00% |  |  |  |
Maximum |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Annual dividend growth rate, percentage |  |  |  |  | 9.00% |  |  |  |
Long-term incentive plans |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Long-term incentive plans (in shares) |  |  |  |  |  |  | 14,862,069 |  |

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