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Earnings per Share - Summary of Buyback Activity by Program (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 12 Months Ended
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May 31, 2019 | May 31, 2018 | May 31, 2017
Equity, Class of Treasury Stock [Line Items] |  |  |
Purchase Price | $ 1,016,300 | $ 127,319 | $ 20,724
Share Repurchase Programs |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Shares | 4,803 | 518 | 39
Avg. Price per Share (in dollars per share) | $ 198.53 | $ 173.51 | $ 94.09
Purchase Price | $ 953,445 | $ 89,997 | $ 3,691
August 4, 2015 |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Shares | 0 | 0 | 39
Avg. Price per Share (in dollars per share) | $ 0.00 | $ 0.00 | $ 94.09
Purchase Price | $ 0 | $ 0 | $ 3,691
August 2, 2016 |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Shares | 2,130 | 518 | 0
Avg. Price per Share (in dollars per share) | $ 192.55 | $ 173.51 | $ 0.00
Purchase Price | $ 410,003 | $ 89,997 | $ 0
October 30, 2018 |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Shares | 2,673 | 0 | 0
Avg. Price per Share (in dollars per share) | $ 203.30 | $ 0.00 | $ 0.00
Purchase Price | $ 543,442 | $ 0 | $ 0

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