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Common Stock - Narrative (Details) - USD ($) | Jun. 30, 2019 | May 31, 2019 | May 14, 2019 | May 02, 2019 | Feb. 19, 2019
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February 2019 ASR |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |
Accelerated stock repurchase program, shares to be repurchased, dollar amount |  |  |  |  | $ 700,000,000
May 2019 ASR |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |
Accelerated stock repurchase program, shares to be repurchased, dollar amount |  |  | $ 500,000,000 | $ 200,000,000 |
Stock repurchase program, shares authorized | $ 600,000,000 |  |  |  |
Accelerated Share Repurchase Program |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |
Stock repurchase program, shares authorized |  | $ 100,000,000 |  |  |

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