Loans and Allowance for Credit Losses (Schedule of Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 24,892,894	$ 24,885,988
Percent of total loans (in Percent)	100.00%	100.00%
Loans and Leases Receivable, Allowance	$ (158,792)	$ (147,946)
Loans and Leases Receivable, Net Amount, Total	24,734,102	24,738,042
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 16,103,150	$ 15,985,274
Percent of total loans (in Percent)	64.70%	64.30%
1-4 single family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 7,133,615	$ 7,128,834
Percent of total loans (in Percent)	28.60%	28.60%
Government Insured Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 1,656,129	$ 1,771,880
Percent of total loans (in Percent)	6.70%	7.10%
Commercial real estate, Non-owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 5,346,895	$ 5,405,597
Percent of total loans (in Percent)	21.50%	21.70%
Construction and land
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 324,805	$ 294,360
Percent of total loans (in Percent)	1.30%	1.20%
Commercial real estate, Owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 1,863,333	$ 1,890,813
Percent of total loans (in Percent)	7.50%	7.60%
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 6,617,716	$ 6,417,721
Percent of total loans (in Percent)	26.50%	25.90%
Pinnacle Public Finance [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 919,584	$ 912,122
Percent of total loans (in Percent)	3.70%	3.70%
Bridge - franchise finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 239,205	$ 253,774
Percent of total loans (in Percent)	1.00%	1.00%
Bridge - equipment finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 266,715	$ 286,147
Percent of total loans (in Percent)	1.10%	1.10%
Mortgage warehouse lending [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 524,897	$ 524,740
Percent of total loans (in Percent)	2.10%	2.10%
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 8,789,744	$ 8,900,714
Percent of total loans (in Percent)	35.30%	35.70%

The percent of total loans.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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