Loans, Leases and Allowance for Credit Losses - Disaggregation of the Company's ACL on Funded Loans and Loan Balances (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	$ 52,817.0	$ 49,723.0
Individually Evaluated for Credit Loss	859.0	574.0
Loans HFI, net of deferred fees and costs	53,676.0	50,297.0
Collectively Evaluated for Credit Loss	304.5	315.1
Individually Evaluated for Credit Loss	69.3	21.6
Total	373.8	336.7	$ 309.7
Warehouse lending
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	8,207.0	6,618.0
Individually Evaluated for Credit Loss	0.0	0.0
Loans HFI, net of deferred fees and costs	8,207.0	6,618.0
Collectively Evaluated for Credit Loss	6.4	5.8
Individually Evaluated for Credit Loss	0.0	0.0
Total	6.4	5.8	8.4
Municipal & nonprofit
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	1,615.0	1,548.0
Individually Evaluated for Credit Loss	5.0	6.0
Loans HFI, net of deferred fees and costs	1,620.0	1,554.0
Collectively Evaluated for Credit Loss	14.1	13.7
Individually Evaluated for Credit Loss	0.6	1.0
Total	14.7	14.7	15.9
Tech & innovation
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	3,283.0	2,729.0
Individually Evaluated for Credit Loss	100.0	79.0
Loans HFI, net of deferred fees and costs	3,383.0	2,808.0
Collectively Evaluated for Credit Loss	33.6	38.3
Individually Evaluated for Credit Loss	22.3	3.8
Total	55.9	42.1	30.8
Equity fund resources
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	884.0	845.0
Individually Evaluated for Credit Loss	0.0	0.0
Loans HFI, net of deferred fees and costs	884.0	845.0
Collectively Evaluated for Credit Loss	1.6	1.3
Individually Evaluated for Credit Loss	0.0	0.0
Total	1.6	1.3	6.4
Other commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	9,047.0	7,362.0
Individually Evaluated for Credit Loss	128.0	90.0
Loans HFI, net of deferred fees and costs	9,175.0	7,452.0
Collectively Evaluated for Credit Loss	75.5	64.6
Individually Evaluated for Credit Loss	2.3	16.8
Total	77.8	81.4	85.9
CRE - owner occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	1,658.0	1,613.0
Individually Evaluated for Credit Loss	17.0	45.0
Loans HFI, net of deferred fees and costs	1,675.0	1,658.0
Collectively Evaluated for Credit Loss	3.4	6.0
Individually Evaluated for Credit Loss	0.0	0.0
Total	3.4	6.0	7.1
Hotel franchise finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	3,786.0	3,708.0
Individually Evaluated for Credit Loss	29.0	147.0
Loans HFI, net of deferred fees and costs	3,815.0	3,855.0
Collectively Evaluated for Credit Loss	35.3	33.4
Individually Evaluated for Credit Loss	0.0	0.0
Total	35.3	33.4	46.9
Other CRE - non-owner occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	5,830.0	5,838.0
Individually Evaluated for Credit Loss	512.0	136.0
Loans HFI, net of deferred fees and costs	6,342.0	5,974.0
Collectively Evaluated for Credit Loss	90.3	96.0
Individually Evaluated for Credit Loss	44.1	0.0
Total	134.4	96.0	47.4
Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	12,961.0	13,287.0
Individually Evaluated for Credit Loss	0.0	0.0
Loans HFI, net of deferred fees and costs	12,961.0	13,287.0
Collectively Evaluated for Credit Loss	19.7	23.1
Individually Evaluated for Credit Loss	0.0	0.0
Total	19.7	23.1	30.4
Residential - EBO
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	972.0	1,223.0
Individually Evaluated for Credit Loss	0.0	0.0
Loans HFI, net of deferred fees and costs	972.0	1,223.0
Collectively Evaluated for Credit Loss	0.0	0.0
Individually Evaluated for Credit Loss	0.0	0.0
Total	0.0	0.0	0.0
Construction and land development
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	4,401.0	4,791.0
Individually Evaluated for Credit Loss	67.0	71.0
Loans HFI, net of deferred fees and costs	4,468.0	4,862.0
Collectively Evaluated for Credit Loss	21.3	30.4
Individually Evaluated for Credit Loss	0.0	0.0
Total	21.3	30.4	27.4
Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Credit Loss	173.0	161.0
Individually Evaluated for Credit Loss	1.0	0.0
Loans HFI, net of deferred fees and costs	174.0	161.0
Collectively Evaluated for Credit Loss	3.3	2.5
Individually Evaluated for Credit Loss	0.0	0.0
Total	$ 3.3	$ 2.5	$ 3.1

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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