| | 2021-01-31 | 2022-01-31 | 2023-01-31 | 2024-01-31 | 2025-01-31 | 2025-04-30 |
| Amortization Of Securities | | 3000000.0 | -42000000.0 | -149000000.0 | -113000000.0 | |
| Beginning Cash Position | | 1388000000.0 | 1541000000.0 | 1895000000.0 | 2024000000.0 | |
| Capital Expenditure | | -272000000.0 | -365000000.0 | -242000000.0 | -272000000.0 | |
| Capital Expenditure Reported | | -264000000.0 | -364000000.0 | -232000000.0 | -269000000.0 | |
| Cash Flow From Continuing Financing Activities | | 110000000.0 | 1204000000.0 | -268000000.0 | -1150000000.0 | |
| Cash Flow From Continuing Investing Activities | | -1607000000.0 | -2506000000.0 | -1751000000.0 | -1781000000.0 | -2046000000.0 |
| Cash Flow From Continuing Operating Activities | | 1651000000.0 | 1657000000.0 | 2149000000.0 | 2461000000.0 | |
| Change In Account Payable | | 9000000.0 | 86000000.0 | -72000000.0 | 25000000.0 | |
| Change In Accrued Expense | | 51000000.0 | 136000000.0 | -95000000.0 | -41000000.0 | |
| Change In Other Working Capital | | 291000000.0 | 159000000.0 | 151000000.0 | 61000000.0 | |
| Change In Payable | | 9000000.0 | 86000000.0 | -72000000.0 | 25000000.0 | |
| Change In Payables And Accrued Expense | | 60000000.0 | 222000000.0 | -167000000.0 | -16000000.0 | |
| Change In Prepaid Assets | | -35000000.0 | -14000000.0 | 69000000.0 | 50000000.0 | |
| Change In Receivables | | -208000000.0 | -319000000.0 | -87000000.0 | -313000000.0 | |
| Change In Working Capital | | 108000000.0 | 48000000.0 | -34000000.0 | -218000000.0 | |
| Changes In Cash | | 154000000.0 | 355000000.0 | 130000000.0 | -470000000.0 | |
| Common Stock Payments | | 0.0 | -75000000.0 | -423000000.0 | -700000000.0 | |
| Deferred Income Tax | | -22000000.0 | 4000000.0 | -1058000000.0 | 33000000.0 | |
| Deferred Tax | | -22000000.0 | 4000000.0 | -1058000000.0 | 33000000.0 | |
| Depreciation Amortization Depletion | | 344000000.0 | 364000000.0 | 282000000.0 | 326000000.0 | |
| Depreciation And Amortization | | 344000000.0 | 364000000.0 | 282000000.0 | 326000000.0 | |
| Effect Of Exchange Rate Changes | | -1000000.0 | -1000000.0 | -1000000.0 | 0.0 | 1000000.0 |
| End Cash Position | | 1541000000.0 | 1895000000.0 | 2024000000.0 | 1554000000.0 | 987000000.0 |
| Financing Cash Flow | | 110000000.0 | 1204000000.0 | -268000000.0 | -1150000000.0 | |
| Free Cash Flow | | 1379000000.0 | 1292000000.0 | 1907000000.0 | 2189000000.0 | 2319000000.0 |
| Gain Loss On Investment Securities | | -146000000.0 | 31000000.0 | 19000000.0 | 16000000.0 | |
| Income Tax Paid Supplemental Data | | 13000000.0 | 89000000.0 | 39000000.0 | 65000000.0 | |
| Interest Paid Supplemental Data | | 13000000.0 | 60000000.0 | 110000000.0 | 110000000.0 | |
| Investing Cash Flow | | -1607000000.0 | -2506000000.0 | -1751000000.0 | -1781000000.0 | -2046000000.0 |
| Issuance Of Debt | | 0.0 | 2978000000.0 | 0.0 | 0.0 | |
| Long Term Debt Issuance | | 0.0 | 2978000000.0 | 0.0 | 0.0 | |
| Long Term Debt Payments | | -38000000.0 | -1844000000.0 | 0.0 | 0.0 | |
| Net Business Purchase And Sale | | -1190000000.0 | 0.0 | -8000000.0 | -825000000.0 | |
| Net Common Stock Issuance | | 0.0 | -75000000.0 | -423000000.0 | -700000000.0 | |
| Net Income From Continuing Operations | | 29000000.0 | -367000000.0 | 1381000000.0 | 526000000.0 | |
| Net Intangibles Purchase And Sale | | -8000000.0 | -1000000.0 | -10000000.0 | -3000000.0 | |
| Net Investment Properties Purchase And Sale | -6116000.0 | -171000000.0 | -4236000.0 | -4000000.0 | | |
| Net Investment Purchase And Sale | | 26000000.0 | -2141000000.0 | -1501000000.0 | -684000000.0 | |
| Net Issuance Payments Of Debt | | -38000000.0 | 1134000000.0 | 0.0 | 0.0 | |
| Net Long Term Debt Issuance | | -38000000.0 | 1134000000.0 | 0.0 | 0.0 | |
| Net Other Financing Charges | | -463000.0 | -7000000.0 | -22000000.0 | -636000000.0 | |
| Operating Cash Flow | | 1651000000.0 | 1657000000.0 | 2149000000.0 | 2461000000.0 | |
| Operating Gains Losses | | -146000000.0 | 31000000.0 | 19000000.0 | 16000000.0 | 10000000.0 |
| Other Non Cash Items | | 234000000.0 | 324000000.0 | 292000000.0 | 372000000.0 | |
| Proceeds From Stock Option Exercised | | 148000000.0 | 152000000.0 | 177000000.0 | 186000000.0 | |
| Purchase Of Business | | -1190000000.0 | 0.0 | -8000000.0 | -825000000.0 | -313000000.0 |
| Purchase Of Intangibles | | -8000000.0 | -1000000.0 | -10000000.0 | -3000000.0 | |
| Purchase Of Investment | | -2982000000.0 | -7206000000.0 | -6166000000.0 | -4808000000.0 | |
| Purchase Of Investment Properties | -6116000.0 | -171000000.0 | -4236000.0 | -4000000.0 | | |
| Repayment Of Debt | | -38000000.0 | -1844000000.0 | 0.0 | 0.0 | |
| Repurchase Of Capital Stock | | 0.0 | -75000000.0 | -423000000.0 | -700000000.0 | -862000000.0 |
| Sale Of Investment | | 3008000000.0 | 5065000000.0 | 4665000000.0 | 4124000000.0 | |
| Stock Based Compensation | | 1101000000.0 | 1295000000.0 | 1416000000.0 | 1519000000.0 | |
