v3.23.3

Short Term Borrowings And Long-Term Debt - Additional Information (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2023 USD ($) BasisPoint	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Outstanding advances		$ 50.0	$ 15.0
Subordinated Notes
Debt Instrument [Line Items]
Proceeds from issuance of subordinated notes, net of debt issuance expense	$ 30.0
Debt issuance costs	$ 0.6
Maturity date	Jun. 30, 2030
Redemption date		Jun. 30, 2025
Fixed interest rate		5.25%
Debt instrument, frequency of periodic interest payment		quarterly
Debt instrument, description of variable rate basis		The notes have a fixed interest rate of 5.25% per annum for the first five years. Thereafter, the interest rate will reset quarterly to an interest rate per annum equal to a benchmark rate (which is expected to be Three-Month Term SOFR) plus 513 basis points.
Carrying value of subordinated notes		$ 29.8	$ 29.7
Subordinated Notes \| SOFR
Debt Instrument [Line Items]
Debt instrument, interest rate plus basis point \| BasisPoint		513
Investment securities, FHLB stock and commercial and residential real estate mortgage loans
Debt Instrument [Line Items]
Federal Home Loan Bank Advances Collateralized Investment Securities Value		$ 17.5
Mortgage loans collateralized amount		735.7
Amount of available credit		$ 426.6

Debt instrument interest rate plus basis point.

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CapStar Financial Holdings, Inc. 10-Q