Debt Covenant, Threshold of Assets to Lose Tier 1 Treatment

No definition available.

Name:	rnst_DebtCovenantThresholdofAssetstoLoseTier1Treatment
Namespace Prefix:	rnst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Debt Instrument, Par, Percentage

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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+ Details

Name:	us-gaap_DebtInstrumentRedemptionPricePercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Long-Term Debt - Additional Information (Details) - USD ($)		12 Months Ended
	Nov. 23, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Mar. 31, 2022	Oct. 31, 2021
Debt Instrument [Line Items]
Repayments of long-term debt		$ 32,417,000	$ 202,873,000	$ 171,000
Debt prepayment penalty		0	6,123,000	121,000
Subordinated notes
Debt Instrument [Line Items]
Repurchase amount			30,000,000
Carrying Value					$ 30,000,000
Par percentage	100.00%
Redemption price percentage	100.00%
FHLB Advances
Debt Instrument [Line Items]
Repayments of long-term debt		$ 0	150,000,000	0
Debt prepayment penalty			6,123,000	$ 121,000
PHC Statutory Trust I
Debt Instrument [Line Items]
Fixed interest rate		5.49%
Capital Bancorp Capital Trust I
Debt Instrument [Line Items]
Fixed interest rate		4.42%
Junior subordinated notes		$ 108,450,000
Threshold of assets to lose tier 1 treatment		$ 15,000,000,000
First M&F Statutory Trust I
Debt Instrument [Line Items]
Fixed interest rate		4.18%
6.50% Fixed-to-Floating Rate Subordinated Notes \| Subordinated notes
Debt Instrument [Line Items]
Repurchase amount						$ 15,000,000
Interest rate of senior note						6.50%
5.00% Fixed-to-Floating Rate Subordinated Notes \| Subordinated notes
Debt Instrument [Line Items]
Repurchase amount			$ 60,000,000
Interest rate of senior note			5.00%