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Changes in Capital Structure - Schedule of Repurchases Under Share Repurchase Programs (Details) - USD ($) | 1 Months Ended | 2 Months Ended | 3 Months Ended | 7 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Oct. 31, 2019 | Sep. 30, 2019 | Apr. 30, 2019 | Feb. 28, 2019 | Sep. 30, 2019 | Sep. 30, 2019 | Sep. 30, 2019 | Aug. 31, 2019
Schedule of Capitalization, Equity [Line Items] |  |  |  |  |  |  |  |
Total number of shares purchased (in shares) |  |  |  |  |  |  | 33,235,480 |
Stock repurchase program, authorized amount |  |  |  | $ 400,000,000 |  |  |  |
Subsequent Event |  |  |  |  |  |  |  |
Schedule of Capitalization, Equity [Line Items] |  |  |  |  |  |  |  |
Total number of shares purchased (in shares) | 441,112 |  |  |  |  |  |  |
2018 Plan |  |  |  |  |  |  |  |
Schedule of Capitalization, Equity [Line Items] |  |  |  |  |  |  |  |
Total number of shares purchased (in shares) |  |  |  | 6,153,415 |  |  |  |
Average price paid per share (in usd per share) |  |  |  | $ 40,610,000 |  |  |  |
Amounts paid for shares purchased |  |  |  | $ 250,000,000 |  |  |  |
Capital Allocation Plan, Accelerated Repurchase Agreement February 2019 |  |  |  |  |  |  |  |
Schedule of Capitalization, Equity [Line Items] |  |  |  |  |  |  |  |
Total number of shares purchased (in shares) |  |  | 9,438,671 |  | 16,615,479 | 26,054,150 |  |
Average price paid per share (in usd per share) |  |  |  |  |  | $ 38,380,000 |  |
Amounts paid for shares purchased |  |  | $ 400,000,000 |  | $ 600,000,000 | $ 1,000,000,000 |  |
Capital Allocation Plan August 2019 |  |  |  |  |  |  |  |
Schedule of Capitalization, Equity [Line Items] |  |  |  |  |  |  |  |
Total number of shares purchased (in shares) |  | 1,027,915 |  |  |  |  |  |
Average price paid per share (in usd per share) |  | $ 36,990,000 |  |  |  |  |  |
Amounts paid for shares purchased |  | $ 38,000,000 |  |  |  |  |  |
Stock repurchase program, authorized amount |  |  |  |  |  |  |  | $ 250,000,000
Capital Allocation Plan August 2019 | Subsequent Event |  |  |  |  |  |  |  |
Schedule of Capitalization, Equity [Line Items] |  |  |  |  |  |  |  |
Total number of shares purchased (in shares) | 441,112 |  |  |  |  |  |  |
Average price paid per share (in usd per share) | $ 39,100,000 |  |  |  |  |  |  |
Amounts paid for shares purchased | $ 17,000,000 |  |  |  |  |  |  |
Capital Allocation Plan |  |  |  |  |  |  |  |
Schedule of Capitalization, Equity [Line Items] |  |  |  |  |  |  |  |
Total number of shares purchased (in shares) |  |  |  |  |  |  | 33,235,480 |
Amounts paid for shares purchased |  |  |  |  |  |  | $ 1,288,000,000 |
Capital Allocation Plan | Subsequent Event |  |  |  |  |  |  |  |
Schedule of Capitalization, Equity [Line Items] |  |  |  |  |  |  |  |
Total number of shares purchased (in shares) | 33,676,592 |  |  |  |  |  |  |
Amounts paid for shares purchased | $ 1,305,000,000 |  |  |  |  |  |  |

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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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