Fair value of loans contractual interest cash flows.

No definition available.

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- Definition

Fair value of loans contractual principal cash flows amount.

+ References

No definition available.

+ Details

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- Definition

Fair value of loans contractual purchase discount.

+ References

No definition available.

+ Details

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- Definition

Fair value of loans future interest payments.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Loan grades range.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Maximum duration past due for restructured loans to be considered performing.

+ References

No definition available.

+ Details

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- Definition

Restructured loans equal to greater than ninety days past due.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Unfunded commitment.

+ References

No definition available.

+ Details

Name:	rnst_UnfundedCommitment
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Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

+ Details

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

- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

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-Name Accounting Standards Codification

-Topic 310

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-Paragraph 11B

-Subparagraph (g)

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-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

+ Details

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

- Definition

Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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Balance Type:	debit
Period Type:	instant

- Definition

The amount of interest income on impaired and nonperforming loans that is due to the change in present value attributable to the passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 19

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5278-111524

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Balance Type:	credit
Period Type:	duration

- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Balance Type:	debit
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Loans and the Allowance for Loan Losses (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Loans and Allowance for Loan Losses (Textual) [Abstract]
Restructured loans discontinued past due period	90 days	90 days
Restructured loans	$ 0	$ 0
Average recorded investment in impaired loans	107,331,000	123,756,000	137,350,000
Interest income recognized on impaired loans			3,908,000
Allowance for loan losses attributable to restructured loans	42,289,000	47,665,000
Remaining availability under commitments to lend additional funds on restructured loans	0	93,000
Fair value of loans contractual principal cash flows amount	95,081,000	125,086,000
Fair value of loans contractual interest cash flows	5,499,000	9,459,000
Fair value of loans contractual interest payments	2,798,000	3,936,000
Fair value of loans contractual purchase discount	29,635,000	36,014,000
Unfunded commitment	5,184,000rnst_UnfundedCommitment	6,855,000rnst_UnfundedCommitment
Maximum
Loans and Allowance for Loan Losses (Textual) [Abstract]
Loan grades range (loan grade)	9
Minimum
Loans and Allowance for Loan Losses (Textual) [Abstract]
Loan grades range (loan grade)	1
Restructured Loans
Loans and Allowance for Loan Losses (Textual) [Abstract]
Outstanding balance of restructured loans	11,392,000	10,078,000
Allowance for loan losses attributable to restructured loans	$ 1,547,000	$ 2,984,000
Pass \| Maximum
Loans and Allowance for Loan Losses (Textual) [Abstract]
Loan grades range (loan grade)	4
Pass \| Minimum
Loans and Allowance for Loan Losses (Textual) [Abstract]
Loan grades range (loan grade)	1
Watch
Loans and Allowance for Loan Losses (Textual) [Abstract]
Loan grades range (loan grade)	5
Substandard \| Maximum
Loans and Allowance for Loan Losses (Textual) [Abstract]
Loan grades range (loan grade)	9
Substandard \| Minimum
Loans and Allowance for Loan Losses (Textual) [Abstract]
Loan grades range (loan grade)	6