Stock Options and Restricted Shares - Performance Unit Awards Outstanding (Details) - shares		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Named Executive Officers (NEOs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Forfeited by participants		199,633
2021 Performance Unit Award | Tranche 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		0 years
Subsequent holding period per tranche (in years)		0 years
2021 Performance Unit Award | Named Executive Officers (NEOs) | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[1],[2]	89,234
2021 Performance Unit Award | Named Executive Officers (NEOs) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[1],[2]	214,155
2021 Performance Unit Award | Leadership Team other than NEOs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[1]	45,240
2020 Performance Unit Award | Tranche 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		3 years
2020 Performance Unit Award | Tranche 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		2 years
2020 Performance Unit Award | Tranche 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		1 year
2020 Performance Unit Award | Named Executive Officers (NEOs) | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[2]	136,137
2020 Performance Unit Award | Named Executive Officers (NEOs) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[2]	204,220
2020 Performance Unit Award | Leadership Team other than NEOs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded		59,648
2019 Performance Unit Award | Tranche 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		3 years
2019 Performance Unit Award | Tranche 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		2 years
2019 Performance Unit Award | Tranche 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		1 year
2019 Performance Unit Award | Named Executive Officers (NEOs) | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[2]	166,211
2019 Performance Unit Award | Named Executive Officers (NEOs) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[2]	249,343
2019 Performance Unit Award | Leadership Team other than NEOs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded		52,244
2018 Performance Unit Award | Tranche 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		3 years
2018 Performance Unit Award | Tranche 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		2 years
2018 Performance Unit Award | Tranche 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		1 year
2018 Performance Unit Award | Named Executive Officers (NEOs) | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[2]	96,878
2018 Performance Unit Award | Named Executive Officers (NEOs) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[2]	145,339
2018 Performance Unit Award | Leadership Team other than NEOs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded		25,990
2017 Performance Unit Award | Tranche 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		3 years
2017 Performance Unit Award | Tranche 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		2 years
2017 Performance Unit Award | Tranche 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period per tranche (in years)		2 years
Subsequent holding period per tranche (in years)		1 year
2017 Performance Unit Award | Named Executive Officers (NEOs) | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[2]	72,537
2017 Performance Unit Award | Named Executive Officers (NEOs) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[2]	109,339
2017 Performance Unit Award | Leadership Team other than NEOs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded		24,916
2016 Performance Unit Award | Leadership Team other than NEOs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded		133,041
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation		46,332
2015 Performance Unit Award | Leadership Team other than NEOs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded			129,723
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			43,996
Time Based Awards | Named Executive Officers (NEOs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period in years		3 years
Shares awarded		56,864
Restrictions lapsed and shares released to participants		4
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Shares Withheld For Taxes By Associates Leadership Team and Directors		3
Shares Forfeited by participants	[3]	0
Shares Unvested		56,857
Time Based Awards | Associates
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded	[4],[5]	172,009
Restrictions lapsed and shares released to participants	[4],[5]	18
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Shares Withheld For Taxes By Associates Leadership Team and Directors	[4],[5]	18
Shares Forfeited by participants	[4],[5],[6]	5,102
Shares Unvested	[4],[5]	166,871
Time Based Awards | Associates | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period in years		3 years
Time Based Awards | Associates | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period in years		5 years

[1] Performance stock unit awards granted in 2021, if earned, will be settled in shares of Pinnacle Financial Common Stock in the period noted in the table, if the performance criterion included in the applicable performance unit award agreement are met.

[2] The named executive officers are awarded a range of awards that may be earned based on attainment of goals between a target level of performance and a maximum level of performance.

[3] These shares represent forfeitures resulting from recipients whose employment was terminated during the year-to-date period ended March 31, 2021. Dividend equivalents are held in escrow for award recipients for dividends paid prior to the forfeiture restrictions lapsing. Such dividend equivalents are not released from escrow if an award is forfeited.

[4] Groups include employees (referred to as associates above) 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 award. Alternatively, the recipient can pay the withholding taxes in cash. 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 awards to Pinnacle Financial's directors, dividends are placed into escrow until the forfeiture restrictions on such shares lapse.

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

[6] These shares represent forfeitures resulting from recipients whose employment or board membership was terminated during the year-to-date period ended March 31, 2021. 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.