Stock Options, Restricted Shares and Restricted Share Units (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
		Jul. 31, 2015	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017		Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant							1,200,000
Number [Roll Forward]
Outstanding, Beginning Balance (in shares)			178,591	276,468	552,372
Granted (in shares)			0	0	0
Exercised (in shares)			(59,317)	(97,877)	(275,904)	[1]
Forfeited (in shares)			0	0	0
Outstanding, Ending Balance (in shares)			119,274	178,591	276,468
Options exercisable (in shares)							119,274
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Outstanding, Beginning Balance (in dollars per share)			$ 22.77	$ 21.40	$ 20.75
Granted (in dollars per share)			0	0	0
Exercised (in dollars per share)			21.40	18.91	20.09	[1]
Forfeited (in dollars per share)			0	0	0
Outstanding, Ending Balance (in dollars per share)			$ 23.45	$ 22.77	$ 21.40
Options exercisable (in dollars per share)							$ 23.45
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding			2 years 10 months 6 days
Options exercisable			2 years 10 months 6 days
Aggregate intrinsic value [Abstract]
Outstanding	[2]						$ 4,837
Options exercisable	[2]						$ 4,837
Quoted closing price of common stock (in dollars per share)							$ 64.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value			$ 2,300	$ 2,700	$ 12,700
Share-based Compensation [Abstract]
Restricted stock expense			21,226	17,636	19,538
Income tax benefit			5,548	4,610	7,665
Restricted stock expense, net of income tax benefit			$ 15,678	$ 13,026	$ 11,873
Unrecognized restricted share expense							$ 37,400
Weighted average period over which unrecognized restricted share expense will be recognized			1 year 7 months 6 days
Number [Roll Forward]
Unvested, beginning of period (in shares)			692,806	936,135	820,539
Shares awards			245,845	180,450	261,942
Conversion of previously awarded restricted share units to restricted share awards				6,200	43,680
Restrictions lapsed and shares released to associates/directors (in shares)			(348,145)	(400,820)	(292,896)
Shares forfeited (in shares)			(35,210)	(29,159)	(34,020)
Unvested, end of period (in shares)			555,296	692,806	936,135
Grant date weighted average cost [Roll Forward]
Unvested, beginning of period (in dollars per share)			$ 55.19	$ 50.08	$ 36.47
Shares awarded (in dollars per share)			55.25	62.40	67.14
Conversion of restricted share units to restricted share awards (in dollars per share)				67.85	69.40
Restrictions lapsed and shares released to associates/directors (in dollars per share)			40.47	46.33	37.59
Shares forfeited (in dollars per share)			58.22	59.51	54.71
Unvested, end of period (in dollars per share)			$ 57.04	$ 55.19	$ 50.08
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards			245,845	180,450	261,942
Shares forfeited (in shares)			(35,210)	(29,159)	(34,020)
Shares Unvested (in shares)			555,296	692,806	936,135		555,296
Restricted Stock Units [Abstract]
Shares awards			245,845	180,450	261,942
Stock-based compensation expense			$ 21,226	$ 17,636	$ 19,538
BNC Bancorp
Number [Roll Forward]
Shares assumed in connection with acquisition of BNC					136,890
Grant date weighted average cost [Roll Forward]
Shares awarded (in dollars per share)					$ 67.25
Employee Stock Option
Number [Roll Forward]
Outstanding, Ending Balance (in shares)			119,274
Stock Swap
Number [Roll Forward]
Exercised (in shares)				(750)
Aggregate intrinsic value [Abstract]
Number of shares settled during period Stock Swap				277
Time Based Awards 2017 | Associates
Number [Roll Forward]
Shares awards	[3],[4]				248,265
Shares forfeited (in shares)	[4],[5]		(37,904)
Unvested, end of period (in shares)	[4]		102,083
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[3],[4]				248,265
Restrictions lapsed and shares released to participants (in shares)	[4]		76,923
Shares withheld for taxes by participants (in shares)	[4]		31,355
Shares forfeited (in shares)	[4],[5]		(37,904)
Shares Unvested (in shares)	[4]		102,083				102,083
Restricted Stock Units [Abstract]
Shares awards	[3],[4]				248,265
Time Based Awards 2017 | Associates | BNC Bancorp
Number [Roll Forward]
Shares awards	[3],[4],[6]				136,890
Shares forfeited (in shares)	[4],[5],[6]		(1,659)
Unvested, end of period (in shares)	[4],[6]		3,215
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[3],[4],[6]				136,890
Restrictions lapsed and shares released to participants (in shares)	[4],[6]		128,176
Shares withheld for taxes by participants (in shares)	[4],[6]		3,840
Shares forfeited (in shares)	[4],[5],[6]		(1,659)
Shares Unvested (in shares)	[4],[6]		3,215				3,215
Restricted Stock Units [Abstract]
Shares awards	[3],[4],[6]				136,890
Time Based Awards 2017 | Associates | Minimum
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years			3 years
Time Based Awards 2017 | Associates | Maximum
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years			5 years
Time Based Awards 2018 | Associates
Number [Roll Forward]
Shares awards	[3],[4]			147,601
Shares forfeited (in shares)	[4],[5]		(9,375)
Unvested, end of period (in shares)	[4]		110,239
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[3],[4]			147,601
Restrictions lapsed and shares released to participants (in shares)	[4]		20,527
Shares withheld for taxes by participants (in shares)	[4]		7,460
Shares forfeited (in shares)	[4],[5]		(9,375)
Shares Unvested (in shares)	[4]		110,239				110,239
Restricted Stock Units [Abstract]
Shares awards	[3],[4]			147,601
Time Based Awards 2018 | Associates | BNC Bancorp
Number [Roll Forward]
Shares awards	[3],[4],[6]			16,777
Shares forfeited (in shares)	[4],[5],[6]		(942)
Unvested, end of period (in shares)	[4],[6]		10,403
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[3],[4],[6]			16,777
Restrictions lapsed and shares released to participants (in shares)	[4],[6]		3,484
Shares withheld for taxes by participants (in shares)	[4],[6]		1,948
Shares forfeited (in shares)	[4],[5],[6]		(942)
Shares Unvested (in shares)	[4],[6]		10,403				10,403
Restricted Stock Units [Abstract]
Shares awards	[3],[4],[6]			16,777
Time Based Awards 2018 | Associates | Minimum
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years			3 years
Time Based Awards 2018 | Associates | Maximum
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years			5 years
Time Based Awards 2019 | Associates
Number [Roll Forward]
Shares awards	[3],[4]		229,296
Shares forfeited (in shares)	[4],[5]		(13,787)
Unvested, end of period (in shares)	[4]		215,235
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[3],[4]		229,296
Restrictions lapsed and shares released to participants (in shares)	[4]		168
Shares withheld for taxes by participants (in shares)	[4]		106
Shares forfeited (in shares)	[4],[5]		(13,787)
Shares Unvested (in shares)	[4]		215,235				215,235
Restricted Stock Units [Abstract]
Shares awards	[3],[4]		229,296
Time Based Awards 2019 | Associates | Minimum
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years			3 years
Time Based Awards 2019 | Associates | Maximum
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years			5 years
Performance Based Awards 2017 | Leadership Team
Number [Roll Forward]
Shares awards	[3],[7]				43,680
Shares forfeited (in shares)	[5],[7]		0
Unvested, end of period (in shares)	[7]		0
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years	[7]			3 years
Shares awards	[3],[7]				43,680
Restrictions lapsed and shares released to participants (in shares)	[7]		15,054
Shares withheld for taxes by participants (in shares)	[7]		28,626
Shares forfeited (in shares)	[5],[7]		0
Shares Unvested (in shares)	[7]		0				0
Restricted Stock Units [Abstract]
Shares awards	[3],[7]				43,680
Performance Based Awards 2018 | Leadership Team
Number [Roll Forward]
Shares awards	[3],[7]			6,200
Shares forfeited (in shares)	[5],[7]		0
Unvested, end of period (in shares)	[7]		0
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years	[7]		3 years
Shares awards	[3],[7]			6,200
Restrictions lapsed and shares released to participants (in shares)	[7]		4,340
Shares withheld for taxes by participants (in shares)	[7]		1,860
Shares forfeited (in shares)	[5],[7]		0
Shares Unvested (in shares)	[7]		0				0
Restricted Stock Units [Abstract]
Shares awards	[3],[7]			6,200
Outside Director Awards 2017
Number [Roll Forward]
Shares awards	[3],[8]				13,677
Shares forfeited (in shares)	[5],[8]		0
Unvested, end of period (in shares)	[8]		0
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years					1 year
Shares awards	[3],[8]				13,677
Restrictions lapsed and shares released to participants (in shares)	[8]		12,139
Shares withheld for taxes by participants (in shares)	[8]		1,538
Shares forfeited (in shares)	[5],[8]		0
Shares Unvested (in shares)	[8]		0				0
Restricted Stock Units [Abstract]
Shares awards	[3],[8]				13,677
Outside Director Awards 2018
Number [Roll Forward]
Shares awards	[3],[8]			16,072
Shares forfeited (in shares)	[5],[8]		0
Unvested, end of period (in shares)	[8]		0
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years				1 year
Shares awards	[3],[8]			16,072
Restrictions lapsed and shares released to participants (in shares)	[8]		12,783
Shares withheld for taxes by participants (in shares)	[8]		3,289
Shares forfeited (in shares)	[5],[8]		0
Shares Unvested (in shares)	[8]		0				0
Restricted Stock Units [Abstract]
Shares awards	[3],[8]			16,072
Outside Director Awards 2019
Number [Roll Forward]
Shares awards	[3],[8]		16,549
Shares forfeited (in shares)	[5],[8]		0
Unvested, end of period (in shares)	[8]		16,549
Restricted stock grants grouped by similar vesting criteria [Abstract]
Vesting Period in years			1 year
Shares awards	[3],[8]		16,549
Restrictions lapsed and shares released to participants (in shares)	[8]		0
Shares withheld for taxes by participants (in shares)	[8]		0
Shares forfeited (in shares)	[5],[8]		0
Shares Unvested (in shares)	[8]		16,549				16,549
Restricted Stock Units [Abstract]
Shares awards	[3],[8]		16,549
2015 Restricted Share Units | Senior Executive Officers | Minimum
Number [Roll Forward]
Shares awards	[9]		58,200
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		58,200
Restricted Stock Units [Abstract]
Shares awards	[9]		58,200
2015 Restricted Share Units | Senior Executive Officers | Maximum
Number [Roll Forward]
Shares awards	[9]		101,850
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		101,850
Restricted Stock Units [Abstract]
Shares awards	[9]		101,850
2015 Restricted Share Units | Leadership Team
Number [Roll Forward]
Shares awards	[9]		28,378
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		28,378
Restricted Stock Units [Abstract]
Shares awards	[9]		28,378
2016 Restricted Share Units | Senior Executive Officers | Minimum
Number [Roll Forward]
Shares awards	[9]		73,474
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		73,474
Restricted Stock Units [Abstract]
Shares awards	[9]		73,474
2016 Restricted Share Units | Senior Executive Officers | Maximum
Number [Roll Forward]
Shares awards	[9]		110,223
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		110,223
Restricted Stock Units [Abstract]
Shares awards	[9]		110,223
2016 Restricted Share Units | Leadership Team
Number [Roll Forward]
Shares awards	[9]		26,683
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		26,683
Restricted Stock Units [Abstract]
Shares awards	[9]		26,683
2017 Restricted Share Units | Senior Executive Officers | Minimum
Number [Roll Forward]
Shares awards	[9]		72,537
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		72,537
Restricted Stock Units [Abstract]
Shares awards	[9]		72,537
2017 Restricted Share Units | Senior Executive Officers | Maximum
Number [Roll Forward]
Shares awards	[9]		109,339
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		109,339
Restricted Stock Units [Abstract]
Shares awards	[9]		109,339
2017 Restricted Share Units | Leadership Team
Number [Roll Forward]
Shares awards	[9]		24,916
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		24,916
Restricted Stock Units [Abstract]
Shares awards	[9]		24,916
2018 Restricted Share Units | Senior Executive Officers | Minimum
Number [Roll Forward]
Shares awards	[9]		96,878
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		96,878
Restricted Stock Units [Abstract]
Shares awards	[9]		96,878
2018 Restricted Share Units | Senior Executive Officers | Maximum
Number [Roll Forward]
Shares awards	[9]		145,339
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		145,339
Restricted Stock Units [Abstract]
Shares awards	[9]		145,339
2018 Restricted Share Units | Leadership Team
Number [Roll Forward]
Shares awards	[9]		25,990
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		25,990
Restricted Stock Units [Abstract]
Shares awards	[9]		25,990
2019 Restricted Share Units | Senior Executive Officers | Minimum
Number [Roll Forward]
Shares awards	[9]		166,211
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		166,211
Restricted Stock Units [Abstract]
Shares awards	[9]		166,211
2019 Restricted Share Units | Senior Executive Officers | Maximum
Number [Roll Forward]
Shares awards	[9]		249,343
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		249,343
Restricted Stock Units [Abstract]
Shares awards	[9]		249,343
2019 Restricted Share Units | Leadership Team
Number [Roll Forward]
Shares awards	[9]		52,244
Restricted stock grants grouped by similar vesting criteria [Abstract]
Shares awards	[9]		52,244
Restricted Stock Units [Abstract]
Shares awards	[9]		52,244
Non qualified stock options
Number [Roll Forward]
Options exercisable (in shares)							71,714
Incentive stock option
Number [Roll Forward]
Options exercisable (in shares)							47,560
Tranche 2015 | 2015 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			3 years
Tranche 2016 | 2015 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			2 years
Tranche 2016 | 2016 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			3 years
Tranche 2017 | 2015 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			1 year
Tranche 2017 | 2016 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			2 years
Tranche 2017 | 2017 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			3 years
Tranche 2018 | 2016 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			1 year
Tranche 2018 | 2017 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			2 years
Tranche 2018 | 2018 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			3 years
Tranche 2019 | 2017 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			1 year
Tranche 2019 | 2018 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			2 years
Tranche 2019 | 2019 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			3 years
Tranche 2020 | 2018 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			1 year
Tranche 2020 | 2019 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			2 years
Tranche 2021 | 2019 Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Restricted Stock Units [Abstract]
Service period per tranche (in years)			2 years
Subsequent holding period per tranche (in years)			1 year
Equity Incentive Plan 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant							500,000
BNC Bancorp 2013 Omnibus Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant							8,000
CapitalMark Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Acquisitions in Period		858,000

[1] Includes 750 stock options which were exercised in a stock swap transaction which settled in 277 shares of Pinnacle Financial common stock.

[2] The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying awards and the quoted price of Pinnacle Financial Common Stock of $64.00 per common share at December 31, 2019 for the 119,274 options that were in-the-money at December 31, 2019.

[3] Groups include employees (referred to as associates above), the leadership team which includes our named executive officers and other key senior leadership members, and outside directors. When the restricted shares are awarded, a participant receives voting rights and forfeitable dividend rights with respect to the shares, but is not able to transfer the shares until the restrictions have lapsed.  Once the restrictions lapse, the participant is taxed on the value of the award and may elect to sell some shares (or have Pinnacle Financial withhold some shares) to pay the applicable income taxes associated with the vested portion of the award. For time-based vesting restricted share awards, dividends paid on shares for which the forfeiture restrictions do not lapse will be recouped by Pinnacle Financial at the time of termination. For performance-based vesting awards and time-based vesting awards to Pinnacle Financial's executive officers, dividends are placed into escrow until the forfeiture restrictions on such shares lapse.

[4] The forfeiture restrictions on these restricted share awards lapse in equal annual installments on the anniversary date of the grant.

[5] These shares represent forfeitures resulting from recipients whose employment or board membership is terminated during each of the years in the three-year period ended December 31, 2019 or for which the performance criteria applicable to the award are not achieved. Any dividends paid on shares for which the forfeiture restrictions do not lapse will be recouped by Pinnacle Financial at the time of termination or will not be distributed from escrow, as applicable.

[6] Restricted share awards issued to associates that were former associates of BNC and to Pinnacle Financial's Chairman of the Carolinas and Virginia pursuant to legacy BNC incentive plans assumed by Pinnacle Financial.

[7] Reflects conversion of restricted share units issued in prior years to restricted share awards. The forfeiture restrictions on these restricted share awards lapse should Pinnacle Financial achieve certain soundness targets at the end of the fifth year following the grant date. See further details of these awards under the caption "Restricted Share Units" below.

[8] Restricted share awards are issued to the outside members of the board of directors in accordance with their board compensation plan.  Restrictions on those awards granted in 2019 lapse on February 29, 2020 based on each individual board member meeting their attendance goals for the various board and board committee meetings to which each member was scheduled to attend.

[9] The named executive officers are awarded a range of awards that may be earned based on attainment of goals at a target level of performance to the maximum level of performance.