Fair Value of Financial Instruments - Carrying Amount and Estimated Fair Value of Financial Instruments (Details) - USD ($)		Jun. 30, 2017	Dec. 31, 2016
Financial assets:
Securities held-to-maturity		$ 21,322,047	$ 25,233,254
Quoted market prices in an active market (Level 1)
Financial assets:
Securities held-to-maturity		0	0
Loans, net		0	0
Mortgage loans held-for-sale		0	0
Loans held-for-sale		0
Financial liabilities:
Deposits and securities sold under agreements to repurchase		0	0
Federal Home Loan Bank advances		0	0
Subordinated debt and other borrowings		0	0
Off-balance sheet instruments:
Commitments to extend credit	[1]	0	0
Standby letters of credit	[2]	0	0
Models with significant observable market parameters (Level 2)
Financial assets:
Securities held-to-maturity		21,322,000	25,233,000
Loans, net		0	0
Mortgage loans held-for-sale		90,534,000	70,480,000
Loans held-for-sale		11,546,000
Financial liabilities:
Deposits and securities sold under agreements to repurchase		0	0
Federal Home Loan Bank advances		0	0
Subordinated debt and other borrowings		0	0
Off-balance sheet instruments:
Commitments to extend credit	[1]	0	0
Standby letters of credit	[2]	0	0
Models with significant unobservable market parameters (Level 3)
Financial assets:
Securities held-to-maturity		0	0
Loans, net		14,429,187,000	8,178,982,000
Mortgage loans held-for-sale		0	0
Loans held-for-sale		0
Financial liabilities:
Deposits and securities sold under agreements to repurchase		15,483,609,000	8,579,664,000
Federal Home Loan Bank advances		725,312,000	406,491,000
Subordinated debt and other borrowings		445,683,000	328,049,000
Off-balance sheet instruments:
Commitments to extend credit	[1]	2,290,000	383,000
Standby letters of credit	[2]	774,000	740,000
Carrying/ Notional Amount
Financial assets:
Securities held-to-maturity		21,163,000	25,251,000
Loans, net		14,696,820,000	8,390,944,000
Mortgage loans held-for-sale		90,275,000	70,298,000
Loans held-for-sale		11,368,000
Financial liabilities:
Deposits and securities sold under agreements to repurchase		15,962,483,000	8,845,014,000
Federal Home Loan Bank advances		725,230,000	406,304,000
Subordinated debt and other borrowings		465,419,000	350,768,000
Off-balance sheet instruments:
Commitments to extend credit	[1]	5,021,242,000	3,374,269,000
Standby letters of credit	[2]	135,819,000	131,418,000
Estimated Fair Value
Financial assets:
Securities held-to-maturity	[3]	21,322,000	25,233,000
Loans, net	[3]	14,429,187,000	8,178,982,000
Mortgage loans held-for-sale	[3]	90,534,000	70,480,000
Loans held-for-sale	[3]	11,546,000
Financial liabilities:
Deposits and securities sold under agreements to repurchase	[3]	15,483,609,000	8,579,664,000
Federal Home Loan Bank advances	[3]	725,312,000	406,491,000
Subordinated debt and other borrowings	[3]	445,683,000	328,049,000
Off-balance sheet instruments:
Commitments to extend credit	[1],[3]	2,290,000	383,000
Standby letters of credit	[2],[3]	$ 774,000	$ 740,000

[1] At the end of each quarter, Pinnacle Financial evaluates the inherent risks of the outstanding off-balance sheet commitments. In making this evaluation, Pinnacle Financial evaluates the credit worthiness of the borrower, the collateral supporting the commitments and any other factors similar to those used to evaluate the inherent risks of our loan portfolio. Additionally, Pinnacle Financial evaluates the probability that the outstanding commitment will eventually become a funded loan. As a result, at June 30, 2017 and December 31, 2016, Pinnacle Financial included in other liabilities $2.3 million and $383,000, respectively, representing the inherent risks associated with these off-balance sheet commitments.

[2] At June 30, 2017 and December 31, 2016, the fair value of Pinnacle Financial's standby letters of credit was $774,000 and $740,000, respectively. This amount represents the unamortized fee associated with these standby letters of credit and is included in the consolidated balance sheet of Pinnacle Financial and is believed to approximate fair value. This fair value will decrease over time as the existing standby letters of credit approach their expiration dates.

[3] Estimated fair values are consistent with an exit-price concept. The assumptions used to estimate the fair values are intended to approximate those that a market-participant would realize in a hypothetical orderly transaction.