Loans and Allowance (Detail Textuals) (USD $)	Dec. 31, 2012 Loan	Dec. 31, 2011 Loan
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Fair value of loan acquired	$ 2,600,000
Number of troubled debt restructuring	1	3
Total amount of loan identified as troubled debt restructured	43,000	1,300,000
Balance of nonaccrual restructured loans	7,693,000
Accruing restructured loans	$ 3,860,000

Represents the balance of accruing restructured loans.

No definition available.

Name:	rivr_AccruingRestructuredLoans
Namespace Prefix:	rivr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents investment in financing receivables that are balance of nonaccrual restructured loans, included in total nonaccrual loans as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	rivr_BalanceOfNonaccrualRestructuredLoans
Namespace Prefix:	rivr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents amount of fair value of loan acquired.

+ References

No definition available.

+ Details

Name:	rivr_FairValueOfLoanAcquired
Namespace Prefix:	rivr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableGrossAllowanceAndNetAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953676-111524

+ Details

Name:	us-gaap_FinancingReceivableModificationsNumberOfContracts1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6951948&loc=d3e18845-111554

+ Details

Name:	us-gaap_FinancingReceivableModificationsRecordedInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant