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Business Segment Information (Business Segment Financial Results) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2021 | Sep. 30, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Net interest income (expense) |  | $ 461 | $ 475 | $ 465 | $ 443 | $ 469 |  | $ 458 |  | $ 471 |  | $ 513 |  | $ 1,844 | $ 1,911 |  | $ 2,339 |
Provision for credit losses |  | (25) | (42) | (135) | (182) | (17) |  | 5 |  | 138 |  | 411 |  | (384) | 537 |  | 74 |
Noninterest income |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,123 | 1,001 |  | 1,010 |
Noninterest expenses |  | 486 | 465 | 463 | 447 | 465 | [1] | 438 | [1] | 434 | [1] | 417 | [1] | 1,861 | 1,754 | [2] | 1,737 | [2]
Provision (benefit) for income taxes |  | 61 | 70 | 93 | 98 | 65 | [1] | 50 | [1] | 28 | [1] | (19) | [1] | 322 | 124 | [2] | 336 | [2]
Net Income |  | $ 228 | $ 262 | $ 328 | $ 350 | $ 221 | [1] | $ 217 | [1] | $ 118 | [1] | $ (59) | [1] | 1,168 | 497 | [2] | 1,202 | [2]
Net credit-related (recoveries) charge-offs |  |  |  |  |  |  |  |  |  |  |  |  |  | (10) | 196 |  | 107 |
Assets, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 90,152 | 81,146 |  | 71,488 |
Loans, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 49,083 | 51,631 |  | 50,511 |
Deposits, average |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 77,681 | $ 65,038 |  | $ 55,481 |
Return on average assets | [3] |  |  |  |  |  |  |  |  |  |  |  |  | 1.30% | 0.61% | [2] | 1.68% | [2]
Efficiency ratio | [4] |  |  |  |  |  |  |  |  |  |  |  |  | 62.60% | 60.13% | [2] | 51.65% | [2]
Commercial Bank |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net interest income (expense) |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,577 | $ 1,607 |  | $ 1,655 |
Provision for credit losses |  |  |  |  |  |  |  |  |  |  |  |  |  | (346) | 495 |  | 88 |
Noninterest income |  |  |  |  |  |  |  |  |  |  |  |  |  | 663 | 555 |  | 555 |
Noninterest expenses |  |  |  |  |  |  |  |  |  |  |  |  |  | 873 | 815 | [2] | 793 | [2]
Provision (benefit) for income taxes |  |  |  |  |  |  |  |  |  |  |  |  |  | 384 | 184 | [2] | 307 | [2]
Net Income |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,329 | 668 | [2] | 1,022 | [2]
Net credit-related (recoveries) charge-offs |  |  |  |  |  |  |  |  |  |  |  |  |  | (12) | 192 |  | 111 |
Assets, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 43,874 | 45,603 |  | 44,946 |
Loans, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 41,804 | 44,123 |  | 43,477 |
Deposits, average |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 45,587 | $ 36,603 |  | $ 29,047 |
Return on average assets | [3] |  |  |  |  |  |  |  |  |  |  |  |  | 2.71% | 1.47% | [2] | 2.28% | [2]
Efficiency ratio | [4] |  |  |  |  |  |  |  |  |  |  |  |  | 38.98% | 37.70% | [2] | 35.87% | [2]
Retail Bank |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net interest income (expense) |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 565 | $ 503 |  | $ 568 |
Provision for credit losses |  |  |  |  |  |  |  |  |  |  |  |  |  | (5) | 7 |  | (4) |
Noninterest income |  |  |  |  |  |  |  |  |  |  |  |  |  | 123 | 110 |  | 132 |
Noninterest expenses |  |  |  |  |  |  |  |  |  |  |  |  |  | 645 | 607 | [2] | 594 | [2]
Provision (benefit) for income taxes |  |  |  |  |  |  |  |  |  |  |  |  |  | 5 | (3) | [2] | 25 | [2]
Net Income |  |  |  |  |  |  |  |  |  |  |  |  |  | 43 | 2 | [2] | 85 | [2]
Net credit-related (recoveries) charge-offs |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 | 1 |  | 1 |
Assets, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,213 | 3,281 |  | 2,852 |
Loans, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,382 | 2,468 |  | 2,104 |
Deposits, average |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 25,682 | $ 22,832 |  | $ 20,743 |
Return on average assets | [3] |  |  |  |  |  |  |  |  |  |  |  |  | 0.16% | 0.00% | [2] | 0.40% | [2]
Efficiency ratio | [4] |  |  |  |  |  |  |  |  |  |  |  |  | 92.98% | 98.52% | [2] | 84.16% | [2]
Wealth Management |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net interest income (expense) |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 166 | $ 167 |  | $ 183 |
Provision for credit losses |  |  |  |  |  |  |  |  |  |  |  |  |  | (32) | 35 |  | (14) |
Noninterest income |  |  |  |  |  |  |  |  |  |  |  |  |  | 279 | 263 |  | 270 |
Noninterest expenses |  |  |  |  |  |  |  |  |  |  |  |  |  | 317 | 295 | [2] | 282 | [2]
Provision (benefit) for income taxes |  |  |  |  |  |  |  |  |  |  |  |  |  | 36 | 22 | [2] | 44 | [2]
Net Income |  |  |  |  |  |  |  |  |  |  |  |  |  | 124 | 78 | [2] | 141 | [2]
Net credit-related (recoveries) charge-offs |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 3 |  | (5) |
Assets, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,028 | 5,162 |  | 5,083 |
Loans, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,903 | 5,045 |  | 4,935 |
Deposits, average |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,218 | $ 4,402 |  | $ 3,833 |
Return on average assets | [3] |  |  |  |  |  |  |  |  |  |  |  |  | 2.24% | 1.51% | [2] | 2.78% | [2]
Efficiency ratio | [4] |  |  |  |  |  |  |  |  |  |  |  |  | 71.02% | 68.47% | [2] | 62.15% | [2]
Finance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net interest income (expense) |  |  |  |  |  |  |  |  |  |  |  |  |  | $ (471) | $ (384) |  | $ (123) |
Provision for credit losses |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  | 0 |
Noninterest income |  |  |  |  |  |  |  |  |  |  |  |  |  | 41 | 55 |  | 41 |
Noninterest expenses |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 | 2 | [2] | 1 | [2]
Provision (benefit) for income taxes |  |  |  |  |  |  |  |  |  |  |  |  |  | (100) | (78) | [2] | (26) | [2]
Net Income |  |  |  |  |  |  |  |  |  |  |  |  |  | (331) | (253) | [2] | (57) | [2]
Net credit-related (recoveries) charge-offs |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  | 0 |
Assets, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 17,705 | 15,418 |  | 13,903 |
Loans, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  | 0 |
Deposits, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 965 | 1,026 |  | 1,673 |
Other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net interest income (expense) |  |  |  |  |  |  |  |  |  |  |  |  |  | 7 | 18 |  | 56 |
Provision for credit losses |  |  |  |  |  |  |  |  |  |  |  |  |  | (1) | 0 |  | 4 |
Noninterest income |  |  |  |  |  |  |  |  |  |  |  |  |  | 17 | 18 |  | 12 |
Noninterest expenses |  |  |  |  |  |  |  |  |  |  |  |  |  | 25 | 35 | [2] | 67 | [2]
Provision (benefit) for income taxes |  |  |  |  |  |  |  |  |  |  |  |  |  | (3) | (1) | [2] | (14) | [2]
Net Income |  |  |  |  |  |  |  |  |  |  |  |  |  | 3 | 2 | [2] | 11 | [2]
Net credit-related (recoveries) charge-offs |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  | 0 |
Assets, average |  |  |  |  |  |  |  |  |  |  |  |  |  | 20,332 | 11,682 |  | 4,704 |
Loans, average |  |  |  |  |  |  |  |  |  |  |  |  |  | (6) | (5) |  | (5) |
Deposits, average |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 229 | $ 175 |  | $ 185 |
[1] | Recast to reflect the retrospective application of the Corporation's election to change the accounting methodology for certain components of defined pension benefit credit. Refer to Note 1 for further information.
[2] | See Defined Benefit Pension and Other Postretirement Costs in Note 1.
[3] | Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity.
[4] | Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding net losses from securities and a derivative contract tied to the conversion rate of Visa Class B shares.

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