Consolidated Statements of Stockholders' Equity - USD ($) shares in Millions, $ in Millions |
Total |
Common Stock [Member] |
Additional Paid-in Capital [Member] |
Retained Earnings [Member] |
Net Unrealized Loss on AFS Securities [Member] |
Foreign Currency Translation [Member] |
Accumulated Other Comprehensive Loss [Member] |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Beginning balance, Shares at May. 31, 2024 | 360.1 | ||||||||||||||
| Beginning balance at May. 31, 2024 | $ 3,801.0 | $ 3.6 | $ 1,729.5 | $ 2,213.0 | $ (120.7) | $ (24.4) | $ (145.1) | ||||||||
| Net Income (Loss) | 840.8 | 840.8 | |||||||||||||
| Unrealized gains on securities, net of tax expense (benefit) | 57.6 | 57.6 | 57.6 | ||||||||||||
| Reclassification adjustment for realized gains (losses) on securities, net of tax expense | [1] | 0.0 | 0.0 | 0.0 | |||||||||||
| Cash dividends declared | (705.7) | (705.7) | |||||||||||||
| Repurchases of common shares including excise taxes, Shares | [2] | (0.8) | |||||||||||||
| Repurchases of common shares including excise taxes | [2] | (104.5) | $ 0.0 | (4.0) | (100.5) | ||||||||||
| Stock-based compensation costs | 32.9 | 32.9 | |||||||||||||
| Foreign currency translation adjustment | (4.4) | (4.4) | (4.4) | ||||||||||||
| Activity related to equity-based plans, Shares | 0.8 | ||||||||||||||
| Activity related to equity-based plans | 8.0 | $ 0.0 | 31.0 | (23.0) | |||||||||||
| Ending balance, Shares at Nov. 30, 2024 | 360.1 | ||||||||||||||
| Ending balance at Nov. 30, 2024 | 3,925.7 | $ 3.6 | 1,789.4 | 2,224.6 | (63.1) | (28.8) | (91.9) | ||||||||
| Beginning balance, Shares at Aug. 31, 2024 | 359.9 | ||||||||||||||
| Beginning balance at Aug. 31, 2024 | 3,850.4 | $ 3.6 | 1,761.7 | 2,165.4 | (58.9) | (21.4) | (80.3) | ||||||||
| Net Income (Loss) | 413.4 | 413.4 | |||||||||||||
| Unrealized gains on securities, net of tax expense (benefit) | (4.2) | (4.2) | (4.2) | ||||||||||||
| Reclassification adjustment for realized gains (losses) on securities, net of tax expense | [1] | 0.0 | 0.0 | 0.0 | |||||||||||
| Cash dividends declared | (352.9) | (352.9) | |||||||||||||
| Repurchases of common shares including excise taxes | [2] | (0.5) | (0.5) | ||||||||||||
| Stock-based compensation costs | 16.4 | 16.4 | |||||||||||||
| Foreign currency translation adjustment | (7.4) | (7.4) | (7.4) | ||||||||||||
| Activity related to equity-based plans, Shares | 0.2 | ||||||||||||||
| Activity related to equity-based plans | 10.5 | $ 0.0 | 11.3 | (0.8) | |||||||||||
| Ending balance, Shares at Nov. 30, 2024 | 360.1 | ||||||||||||||
| Ending balance at Nov. 30, 2024 | $ 3,925.7 | $ 3.6 | 1,789.4 | 2,224.6 | (63.1) | (28.8) | (91.9) | ||||||||
| Beginning balance, Shares at May. 31, 2025 | 360.5 | 360.5 | |||||||||||||
| Beginning balance at May. 31, 2025 | $ 4,128.0 | $ 3.6 | 1,901.1 | 2,277.0 | (38.5) | (15.2) | (53.7) | ||||||||
| Net Income (Loss) | 779.2 | 779.2 | |||||||||||||
| Unrealized gains on securities, net of tax expense (benefit) | 38.5 | 38.5 | 38.5 | ||||||||||||
| Reclassification adjustment for realized gains (losses) on securities, net of tax expense | [3] | (5.3) | (5.3) | (5.3) | |||||||||||
| Cash dividends declared | (777.0) | (777.0) | |||||||||||||
| Repurchases of common shares including excise taxes, Shares | [4] | (2.1) | |||||||||||||
| Repurchases of common shares including excise taxes | [4] | (286.6) | $ 0.0 | (10.2) | (276.4) | ||||||||||
| Stock-based compensation costs | 52.3 | 52.3 | |||||||||||||
| Foreign currency translation adjustment | 2.9 | 2.9 | 2.9 | ||||||||||||
| Activity related to equity-based plans, Shares | 0.6 | ||||||||||||||
| Activity related to equity-based plans | $ (51.9) | $ 0.0 | 0.9 | (52.8) | |||||||||||
| Ending balance, Shares at Nov. 30, 2025 | 359.0 | 359.0 | |||||||||||||
| Ending balance at Nov. 30, 2025 | $ 3,880.1 | $ 3.6 | 1,944.1 | 1,950.0 | (5.3) | (12.3) | (17.6) | ||||||||
| Beginning balance, Shares at Aug. 31, 2025 | 359.9 | ||||||||||||||
| Beginning balance at Aug. 31, 2025 | 3,970.6 | $ 3.6 | 1,921.8 | 2,070.2 | (14.2) | (10.8) | (25.0) | ||||||||
| Net Income (Loss) | 395.4 | 395.4 | |||||||||||||
| Unrealized gains on securities, net of tax expense (benefit) | 14.2 | 14.2 | 14.2 | ||||||||||||
| Reclassification adjustment for realized gains (losses) on securities, net of tax expense | [3] | (5.3) | (5.3) | (5.3) | |||||||||||
| Cash dividends declared | (388.0) | (388.0) | |||||||||||||
| Repurchases of common shares including excise taxes, Shares | [4] | (1.0) | |||||||||||||
| Repurchases of common shares including excise taxes | [4] | (126.5) | $ 0.0 | (4.9) | (121.6) | ||||||||||
| Stock-based compensation costs | 25.5 | 25.5 | |||||||||||||
| Foreign currency translation adjustment | (1.5) | (1.5) | (1.5) | ||||||||||||
| Activity related to equity-based plans, Shares | 0.1 | ||||||||||||||
| Activity related to equity-based plans | $ (4.3) | $ 0.0 | 1.7 | (6.0) | |||||||||||
| Ending balance, Shares at Nov. 30, 2025 | 359.0 | 359.0 | |||||||||||||
| Ending balance at Nov. 30, 2025 | $ 3,880.1 | $ 3.6 | $ 1,944.1 | $ 1,950.0 | $ (5.3) | $ (12.3) | $ (17.6) | ||||||||
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