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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from seven to eleven years of the Balance Sheet date.

No definition available.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from three to seven years of the Balance Sheet date.

No definition available.

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Amount of federal home loan bank advances maturing in eleven to thirteen year following the latest fiscal year.

No definition available.

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Amount of federal home loan bank advances maturing in seven to eleven year following the latest fiscal year.

No definition available.

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Amount of federal home loan bank advances maturing in three to seven year following the latest fiscal year.

No definition available.

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Namespace Prefix:	nvsl_
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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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The calculated weighted average interest rate for Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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 210.9-03.13(3)(a))

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

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- Details

Name:	us-gaap_FederalHomeLoanBankAdvancesBranchOfFHLBBankLineItems
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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due within one year of the Balance Sheet date.

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

-Publisher SEC

-Name Industry Guide

-Number 3

-Section VII.3

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from one to two years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from two to three years of the Balance Sheet date.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Amount of federal home loan bank advances maturing in the second fiscal year following the latest fiscal year.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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Amount of federal home loan bank advances maturing in the third fiscal year following the latest fiscal year.

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Amount of federal home loan bank advances maturing in the next fiscal year following the latest fiscal year.