Percentage, before allowance for credit loss, of financing receivable to total financing receivable.

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Loans and Allowance for Credit Losses (Schedule of Loans) (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 23,929,073		$ 24,273,707
Allowance for credit losses	(217,516)	$ (208,790)	(219,825)	$ (222,730)	$ (219,747)	$ (223,153)
Loans, net	$ 23,711,557		$ 24,053,882
Percent of Total Loans	100.00%		100.00%
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 17,273,523		$ 17,290,707
Allowance for credit losses	$ (205,141)	(198,459)	$ (208,412)	(208,961)	(204,180)	(211,203)
Percent of Total Loans	72.20%		71.20%
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 6,655,550		$ 6,983,000
Allowance for credit losses	$ (12,375)	$ (10,331)	$ (11,413)	$ (13,769)	$ (15,567)	$ (11,950)
Percent of Total Loans	27.80%		28.80%
Non-owner occupied commercial real estate \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 6,327,275		$ 6,105,207
Percent of Total Loans	26.40%		25.20%
Construction and land \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 679,626		$ 705,664
Percent of Total Loans	2.80%		2.90%
Owner occupied commercial real estate \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 2,039,523		$ 2,020,572
Percent of Total Loans	8.50%		8.30%
Commercial and industrial \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 6,641,643		$ 7,008,903
Percent of Total Loans	27.80%		28.80%
Pinnacle - municipal finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 636,945		$ 619,374
Pinnacle - municipal finance \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 636,945		$ 619,374
Percent of Total Loans	2.70%		2.60%
Franchise and equipment finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 71,740		$ 102,746
Franchise and equipment finance \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 71,740		$ 102,746
Percent of Total Loans	0.30%		0.40%
Mortgage warehouse lending
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 876,771		$ 728,241
Mortgage warehouse lending \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 876,771		$ 728,241
Percent of Total Loans	3.70%		3.00%
1-4 single family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 5,807,912		$ 6,091,959
1-4 single family residential \| Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 5,807,912		$ 6,091,959
Percent of Total Loans	24.30%		25.10%
Government insured residential \| Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 847,638		$ 891,041
Percent of Total Loans	3.50%		3.70%