Regulatory Matters (Details) $ / shares in Units, shares in Thousands		3 Months Ended
		Mar. 31, 2024 USD ($) $ / shares	Jun. 30, 2020 shares	Dec. 31, 2023 USD ($)		Dec. 31, 2021 $ / shares
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Preceding period of retained earnings used in calculation of dividend payable		2 years
Retained earnings		$ 2,887,804,000		$ 2,784,927,000
Quarterly common stock dividend (in dollar per share) | $ / shares		$ 0.22				$ 0.18
Depositary Shares | shares			9,000
Preferred Stock, Dividend Rate, Per-Dollar-Amount | $ / shares		$ 16.88
Preferred Stock, Dividend Per Depositary Share		$ 0.422
Pinnacle Financial
Actual
Total capital to risk weighted assets		5,232,720,000		5,115,755,000
Tier I capital to risk weighted assets		4,433,585,000		4,354,759,000
Common equity Tier 1 capital to risk weighted assets		4,216,336,000		4,137,510,000
Tier I capital to average assets	[1]	$ 4,433,585,000		$ 4,354,759,000
Actual
Total capital to risk weighted assets (as percent)		0.129		0.127
Tier I capital to risk weighted assets (as percent)		0.109		0.108
Common equity Tier 1 capital to risk weighted assets		0.104		0.103
Tier I capital to average assets (as percent)	[1]	0.094		0.094
Minimum Capital Requirement
Total capital to risk weighted assets		$ 3,242,505,000		$ 3,216,424,000
Tier I capital to risk weighted assets		2,431,879,000		2,412,318,000
Common equity Tier 1 capital to risk weighted assets		1,823,909,000		1,809,238,000
Tier I capital to average assets	[1]	$ 1,876,133,000		$ 1,853,213,000
Minimum Capital Requirement
Total capital to risk weighted assets (as percent)		0.080		0.080
Tier I capital to risk weighted assets (as percent)		0.060		0.060
Common Equity Tier I capital to risk weighted assets (as percent)		0.045		0.045
Tier I capital to average assets (as percent)	[1]	0.040		0.040
Minimum To Be Well-Capitalized (1)
Total capital to risk weighted assets		$ 4,053,131,000		$ 4,020,530,000	[2]
Tier I capital to risk weighted assets	[2]	$ 2,431,879,000		$ 2,412,318,000
Minimum To Be Well-Capitalized (1)
Total capital to risk weighted assets (as percent)		0.100		0.100	[2]
Tier I capital to risk weighted assets (as percent)	[2]	0.060		0.060
Pinnacle Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Cash dividends paid to Pinnacle Financial by Pinnacle Bank		$ 26,700,000
Retained earnings		1,100,000,000
Actual
Total capital to risk weighted assets		4,924,981,000		$ 4,797,278,000
Tier I capital to risk weighted assets		4,554,846,000		4,465,282,000
Common equity Tier 1 capital to risk weighted assets		4,554,723,000		4,465,159,000
Tier I capital to average assets	[1]	$ 4,554,846,000		$ 4,465,282,000
Actual
Total capital to risk weighted assets (as percent)		0.122		0.120
Tier I capital to risk weighted assets (as percent)		0.113		0.111
Common equity Tier 1 capital to risk weighted assets		0.113		0.111
Tier I capital to average assets (as percent)	[1]	0.097		0.097
Minimum Capital Requirement
Total capital to risk weighted assets		$ 3,234,396,000		$ 3,207,699,000
Tier I capital to risk weighted assets		2,425,797,000		2,405,774,000
Common equity Tier 1 capital to risk weighted assets		1,819,348,000		1,804,330,000
Tier I capital to average assets	[1]	$ 1,871,699,000		$ 1,847,972,000
Minimum Capital Requirement
Total capital to risk weighted assets (as percent)		0.080		0.080
Tier I capital to risk weighted assets (as percent)		0.060		0.060
Common Equity Tier I capital to risk weighted assets (as percent)		0.045		0.045
Tier I capital to average assets (as percent)	[1]	0.040		0.040
Minimum To Be Well-Capitalized (1)
Total capital to risk weighted assets		$ 4,042,995,000		$ 4,009,623,000	[2]
Tier I capital to risk weighted assets	[2]	3,234,396,000		3,207,699,000
Common equity Tier 1 capital to risk weighted assets	[2]	2,627,947,000		2,606,255,000
Tier I capital to average assets	[1],[2]	$ 2,339,624,000		$ 2,309,965,000
Minimum To Be Well-Capitalized (1)
Total capital to risk weighted assets (as percent)		0.100		0.100	[2]
Tier I capital to risk weighted assets (as percent)	[2]	0.080		0.080
Common Equity Tier I capital to risk weighted assets (as percent)	[2]	0.065		0.065
Tier I capital to average assets (as percent)	[1],[2]	0.050		0.050

[1] (*) Average assets for the above calculations were based on the most recent quarter.

[2] Well-capitalized minimum Common equity Tier 1 capital to risk weighted assets and Tier 1 capital to average assets are not formally defined under applicable banking regulations for bank holding companies.