Deferred loan origination fees incurred at the end of period.

No definition available.

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Namespace Prefix:	nvsl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of undisbursed construction loan to cover probable credit losses on loans and leases.

+ References

No definition available.

+ Details

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Namespace Prefix:	nvsl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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))

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-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 4: 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

+ Details

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

- 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. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

Reference 2: 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)

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

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Balance Type:	debit
Period Type:	instant

LOANS RECEIVABLE (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012	Dec. 31, 2011
Loans Receivable [Line Items]
Total loans	$ 402,126	$ 434,006	$ 455,679
Allowance for loan losses	10,746	14,500	10,972	8,053
Undisbursed construction loans	2,012	1,724
Deferred loan origination fees, net	120	169
Loans receivable, net	389,248	417,613
Commercial business loans [Member]
Loans Receivable [Line Items]
Total loans	28,007	32,970
Real Estate [Member]
Loans Receivable [Line Items]
Total loans	346,774	370,910
Real Estate [Member] \| One to four family [Member]
Loans Receivable [Line Items]
Total loans	205,685	209,004
Real Estate [Member] \| Commercial Real Estate and Multi-Family [Member]
Loans Receivable [Line Items]
Total loans	129,789	133,549
Real Estate [Member] \| Construction Loans [Member]
Loans Receivable [Line Items]
Total loans	11,300	28,357
Consumer Loan [Member]
Loans Receivable [Line Items]
Total loans	27,345	30,126
Consumer Loan [Member] \| Home Equity Line of Credit [Member]
Loans Receivable [Line Items]
Total loans	26,420	28,829
Consumer Loan [Member] \| Other consumer [Member]
Loans Receivable [Line Items]
Total loans	$ 925	$ 1,297