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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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Loans and Allowance for Credit Losses (Schedule of Loans) (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 23,702,494		$ 24,297,980
Allowance for credit losses	(219,884)	$ (222,730)	(223,153)	$ (228,249)	$ (225,698)	$ (202,689)
Loans, net	$ 23,482,610		$ 24,074,827
Percent of Total Loans	100.00%		100.00%
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 16,571,502		$ 16,717,166
Allowance for credit losses	$ (206,712)	(208,961)	$ (211,203)	(216,519)	(219,472)	(195,058)
Percent of Total Loans	69.90%		68.80%
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 7,130,992		$ 7,580,814
Allowance for credit losses	$ (13,172)	$ (13,769)	$ (11,950)	$ (11,730)	$ (6,226)	$ (7,631)
Percent of Total Loans	30.10%		31.20%
Non-owner occupied commercial real estate \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 5,820,343		$ 5,652,203
Percent of Total Loans	24.60%		23.30%
Construction and land \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 714,272		$ 561,989
Percent of Total Loans	3.00%		2.30%
Owner occupied commercial real estate \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 1,943,331		$ 1,941,004
Percent of Total Loans	8.20%		8.00%
Commercial and industrial \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 6,612,538		$ 7,042,222
Percent of Total Loans	27.80%		28.90%
Pinnacle - municipal finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 637,198		$ 720,661
Pinnacle - municipal finance \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 637,198		$ 720,661
Percent of Total Loans	2.70%		3.00%
Franchise and equipment finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 134,635		$ 213,477
Franchise and equipment finance \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 134,635		$ 213,477
Percent of Total Loans	0.60%		0.90%
Mortgage warehouse lending
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 709,185		$ 585,610
Mortgage warehouse lending \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 709,185		$ 585,610
Percent of Total Loans	3.00%		2.40%
1-4 single family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 6,199,657		$ 6,508,922
1-4 single family residential \| Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 6,199,657		$ 6,508,922
Percent of Total Loans	26.20%		26.80%
Government insured residential \| Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 931,335		$ 1,071,892
Percent of Total Loans	3.90%		4.40%