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Loans and Leases (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Dec. 31, 2016	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans pledged to secure borrowings		$ 7,300		$ 7,300		$ 5,200
Loans and leases, deferred fees and costs		58		58		62
Discounts on acquired loans		760		760		439
Principal Balance of Loan		48,462		48,462		37,681
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss		47,989		47,989		37,256
Proceeds from Sale of Loans Receivable				43	$ 115
Interest income recognized on leases		6	$ 6	17	$ 16
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Loss [Line Items]
Principal Balance of Loan		569		569		200
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss		506		506		179
Asset Pledged as Collateral
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans pledged to secure borrowings		$ 31,000		$ 31,000		22,000
Minimum
Financing Receivable, Allowance for Credit Loss [Line Items]
Lease term		3 years		3 years
Maximum
Financing Receivable, Allowance for Credit Loss [Line Items]
Lease term		5 years		5 years
Loans [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Interest Receivable		$ 191		$ 191		$ 148
Multifamily Loan Securitization [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans To Others Outstanding Balance		$ 32		$ 32
Multifamily Loan Securitization [Member] | Pacific Premier Bancorp
Financing Receivable, Allowance for Credit Loss [Line Items]
Proceeds from Sale of Loans Receivable	$ 509

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