Loans and Allowance for Credit Losses - Loan Classification by Risk Rating Category (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
2023		$ 6,269,411		$ 6,269,411
2022		9,128,677		9,128,677
2021		6,093,393		6,093,393
2020		2,240,004		2,240,004
2019		1,371,261		1,371,261
Prior		1,402,642		1,402,642
Revolving Loans		5,437,896		5,437,896
Total		31,943,284		31,943,284		$ 29,041,605
Charged-off loans		(24,709)	$ (17,699)	(57,616)	$ (33,384)
2023
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(2,199)
2022
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(20,808)
2021
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(15,156)
2020
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(2,875)
2019
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(277)
Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(746)
Revolving Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(15,555)
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023		6,196,447		6,196,447
2022		9,013,243		9,013,243
2021		6,010,248		6,010,248
2020		2,212,710		2,212,710
2019		1,355,366		1,355,366
Prior		1,374,195		1,374,195
Revolving Loans		5,314,796		5,314,796
Total		31,477,005		31,477,005
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023		19,750		19,750
2022		95,598		95,598
2021		34,263		34,263
2020		16,790		16,790
2019		5,812		5,812
Prior		12,792		12,792
Revolving Loans		70,409		70,409
Total		255,414		255,414
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023	[1]	41,707		41,707
2022	[1]	13,122		13,122
2021	[1]	44,353		44,353
2020	[1]	3,636		3,636
2019	[1]	3,279		3,279
Prior	[1]	10,334		10,334
Revolving Loans	[1]	51,484		51,484
Total	[1]	167,915		167,915
Substandard-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		11,507		11,507
2022		6,714		6,714
2021		4,529		4,529
2020		6,868		6,868
2019		6,804		6,804
Prior		5,321		5,321
Revolving Loans		1,207		1,207
Total		42,950		42,950
Doubtful-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		0		0
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		0		0
Commercial real estate - owner occupied
Financing Receivable, Credit Quality Indicator [Line Items]
2023		572,971		572,971
2022		1,188,616		1,188,616
2021		872,932		872,932
2020		526,145		526,145
2019		305,406		305,406
Prior		415,418		415,418
Revolving Loans		63,128		63,128
Total		3,944,616		3,944,616		3,587,257
Charged-off loans		0	(447)	0	(1,412)
Commercial real estate - owner occupied | 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - owner occupied | 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - owner occupied | 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - owner occupied | 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - owner occupied | 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - owner occupied | Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - owner occupied | Revolving Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - owner occupied | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023		564,968		564,968
2022		1,140,655		1,140,655
2021		869,651		869,651
2020		518,137		518,137
2019		299,408		299,408
Prior		410,623		410,623
Revolving Loans		47,514		47,514
Total		3,850,956		3,850,956
Commercial real estate - owner occupied | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023		1,489		1,489
2022		38,361		38,361
2021		238		238
2020		3,986		3,986
2019		5,429		5,429
Prior		3,089		3,089
Revolving Loans		15,614		15,614
Total		68,206		68,206
Commercial real estate - owner occupied | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023	[1]	5,528		5,528
2022	[1]	8,940		8,940
2021	[1]	3,043		3,043
2020	[1]	1,662		1,662
2019	[1]	569		569
Prior	[1]	621		621
Revolving Loans	[1]	0		0
Total	[1]	20,363		20,363
Commercial real estate - owner occupied | Substandard-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		986		986
2022		660		660
2021		0		0
2020		2,360		2,360
2019		0		0
Prior		1,085		1,085
Revolving Loans		0		0
Total		5,091		5,091
Commercial real estate - owner occupied | Doubtful-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		0		0
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		0		0
Commercial real estate - non-owner occupied
Financing Receivable, Credit Quality Indicator [Line Items]
2023		1,034,531		1,034,531
2022		2,696,586		2,696,586
2021		1,761,776		1,761,776
2020		786,584		786,584
2019		591,154		591,154
Prior		466,482		466,482
Revolving Loans		110,497		110,497
Total		7,447,610		7,447,610		6,542,619
Charged-off loans		0	(99)	0	(284)
Commercial real estate - non-owner occupied | 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - non-owner occupied | 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - non-owner occupied | 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - non-owner occupied | 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - non-owner occupied | 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - non-owner occupied | Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - non-owner occupied | Revolving Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Commercial real estate - non-owner occupied | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023		1,005,075		1,005,075
2022		2,663,004		2,663,004
2021		1,721,620		1,721,620
2020		779,796		779,796
2019		589,720		589,720
Prior		458,572		458,572
Revolving Loans		110,497		110,497
Total		7,328,284		7,328,284
Commercial real estate - non-owner occupied | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023		3,174		3,174
2022		30,455		30,455
2021		0		0
2020		6,788		6,788
2019		218		218
Prior		7,348		7,348
Revolving Loans		0		0
Total		47,983		47,983
Commercial real estate - non-owner occupied | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023	[1]	24,641		24,641
2022	[1]	2,974		2,974
2021	[1]	40,156		40,156
2020	[1]	0		0
2019	[1]	1,216		1,216
Prior	[1]	562		562
Revolving Loans	[1]	0		0
Total	[1]	69,549		69,549
Commercial real estate - non-owner occupied | Substandard-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		1,641		1,641
2022		153		153
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		1,794		1,794
Commercial real estate - non-owner occupied | Doubtful-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		0		0
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		0		0
Consumer real estate – mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
2023		507,540		507,540
2022		992,204		992,204
2021		1,065,222		1,065,222
2020		459,996		459,996
2019		219,415		219,415
Prior		333,044		333,044
Revolving Loans		1,191,359		1,191,359
Total		4,768,780		4,768,780		4,435,046
Charged-off loans		(168)	(155)	(598)	(409)
Consumer real estate – mortgage | 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Consumer real estate – mortgage | 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(85)
Consumer real estate – mortgage | 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(80)
Consumer real estate – mortgage | 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(6)
Consumer real estate – mortgage | 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(49)
Consumer real estate – mortgage | Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(378)
Consumer real estate – mortgage | Revolving Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Consumer real estate – mortgage | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023		507,284		507,284
2022		990,832		990,832
2021		1,062,479		1,062,479
2020		455,584		455,584
2019		212,988		212,988
Prior		329,196		329,196
Revolving Loans		1,190,763		1,190,763
Total		4,749,126		4,749,126
Consumer real estate – mortgage | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		0		0
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		0		0
Consumer real estate – mortgage | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023	[1]	0		0
2022	[1]	0		0
2021	[1]	0		0
2020	[1]	0		0
2019	[1]	0		0
Prior	[1]	0		0
Revolving Loans	[1]	0		0
Total	[1]	0		0
Consumer real estate – mortgage | Substandard-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		256		256
2022		1,372		1,372
2021		2,743		2,743
2020		4,412		4,412
2019		6,427		6,427
Prior		3,848		3,848
Revolving Loans		596		596
Total		19,654		19,654
Consumer real estate – mortgage | Doubtful-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		0		0
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		0		0
Construction and land development
Financing Receivable, Credit Quality Indicator [Line Items]
2023		892,096		892,096
2022		1,859,960		1,859,960
2021		1,055,716		1,055,716
2020		73,342		73,342
2019		12,317		12,317
Prior		7,221		7,221
Revolving Loans		41,491		41,491
Total		3,942,143		3,942,143		3,679,498
Charged-off loans		(3)	0	(3)	(150)
Construction and land development | 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Construction and land development | 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Construction and land development | 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Construction and land development | 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Construction and land development | 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Construction and land development | Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(3)
Construction and land development | Revolving Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				0
Construction and land development | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023		888,677		888,677
2022		1,843,853		1,843,853
2021		1,054,829		1,054,829
2020		69,024		69,024
2019		12,317		12,317
Prior		7,138		7,138
Revolving Loans		41,491		41,491
Total		3,917,329		3,917,329
Construction and land development | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023		3,419		3,419
2022		16,107		16,107
2021		887		887
2020		4,318		4,318
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		24,731		24,731
Construction and land development | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023	[1]	0		0
2022	[1]	0		0
2021	[1]	0		0
2020	[1]	0		0
2019	[1]	0		0
Prior	[1]	83		83
Revolving Loans	[1]	0		0
Total	[1]	83		83
Construction and land development | Substandard-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		0		0
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		0		0
Construction and land development | Doubtful-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		0		0
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		0		0
Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
2023		3,125,948		3,125,948
2022		2,358,348		2,358,348
2021		1,265,506		1,265,506
2020		353,194		353,194
2019		242,257		242,257
Prior		179,725		179,725
Revolving Loans		3,782,633		3,782,633
Total		11,307,611		11,307,611		10,241,362
Charged-off loans		(20,330)	(13,029)	(45,158)	(22,684)
Commercial and industrial | 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(2,170)
Commercial and industrial | 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(20,287)
Commercial and industrial | 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(9,840)
Commercial and industrial | 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(686)
Commercial and industrial | 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(88)
Commercial and industrial | Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(301)
Commercial and industrial | Revolving Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(11,786)
Commercial and industrial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023		3,094,118		3,094,118
2022		2,341,941		2,341,941
2021		1,229,428		1,229,428
2020		349,426		349,426
2019		240,221		240,221
Prior		167,914		167,914
Revolving Loans		3,675,820		3,675,820
Total		11,098,868		11,098,868
Commercial and industrial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023		11,668		11,668
2022		10,675		10,675
2021		33,138		33,138
2020		1,698		1,698
2019		165		165
Prior		2,355		2,355
Revolving Loans		54,795		54,795
Total		114,494		114,494
Commercial and industrial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023	[1]	11,538		11,538
2022	[1]	1,208		1,208
2021	[1]	1,154		1,154
2020	[1]	1,974		1,974
2019	[1]	1,494		1,494
Prior	[1]	9,068		9,068
Revolving Loans	[1]	51,484		51,484
Total	[1]	77,920		77,920
Commercial and industrial | Substandard-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		8,624		8,624
2022		4,524		4,524
2021		1,786		1,786
2020		96		96
2019		377		377
Prior		388		388
Revolving Loans		534		534
Total		16,329		16,329
Commercial and industrial | Doubtful-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		0		0
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		0		0
Consumer and other
Financing Receivable, Credit Quality Indicator [Line Items]
2023		136,325		136,325
2022		32,963		32,963
2021		72,241		72,241
2020		40,743		40,743
2019		712		712
Prior		752		752
Revolving Loans		248,788		248,788
Total		532,524		532,524		$ 555,823
Charged-off loans		(4,208)	$ (3,969)	(11,857)	$ (8,445)
Consumer and other | 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(29)
Consumer and other | 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(436)
Consumer and other | 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(5,236)
Consumer and other | 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(2,183)
Consumer and other | 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(140)
Consumer and other | Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(64)
Consumer and other | Revolving Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Charged-off loans				(3,769)
Consumer and other | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023		136,325		136,325
2022		32,958		32,958
2021		72,241		72,241
2020		40,743		40,743
2019		712		712
Prior		752		752
Revolving Loans		248,711		248,711
Total		532,442		532,442
Consumer and other | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		0		0
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		0		0
Consumer and other | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023	[1]	0		0
2022	[1]	0		0
2021	[1]	0		0
2020	[1]	0		0
2019	[1]	0		0
Prior	[1]	0		0
Revolving Loans	[1]	0		0
Total	[1]	0		0
Consumer and other | Substandard-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		5		5
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		77		77
Total		82		82
Consumer and other | Doubtful-nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023		0		0
2022		0		0
2021		0		0
2020		0		0
2019		0		0
Prior		0		0
Revolving Loans		0		0
Total		$ 0		$ 0

[1] Potential problem loans represent those loans with a well-defined weakness and where information about possible credit problems of borrowers has caused management to have doubts about the borrower's ability to comply with present repayment terms. This definition is believed to be substantially consistent with the standards established by Pinnacle Bank's primary regulators for loans classified as substandard, excluding loan modifications made to borrowers experiencing financial difficulty. Potential problem loans, which are not included in nonaccrual loans, amounted to approximately $134.5 million at September 30, 2023, compared to $53.8 million at December 31, 2022.