Premises, Equipment and Software (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Land	$ 269	$ 264
Buildings	959	943
Furniture and equipment	336	346
Leasehold improvements	137	151
Software	749	730
Total	2,450	2,434
Less accumulated depreciation and amortization	1,050	1,026
Net book value	1,400	1,408
Capitalized costs	$ 40	$ 298

Additions made to capitalized computer software costs during the period.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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Amount before accumulated depreciation of fixtures and equipment. Includes, but is not limited to, machinery, equipment, and engines.

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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Amount of accumulated depreciation and amortization from plant, property, and equipment and right-of-use asset from finance lease.

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Amount, after accumulated depreciation and amortization, of property, plant, and equipment and finance lease right-of-use asset.

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Amount, before accumulated depreciation and amortization, of property, plant, and equipment and finance lease right-of-use asset.

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