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Period Type:	instant

- References

No definition available.

Name:	nvsl_DepositsLineItems
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Data Type:	xbrli:stringItemType
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The aggregate of all domestic and foreign interest-bearing deposit liabilities.

No definition available.

Name:	nvsl_DepositsPercentage
Namespace Prefix:	nvsl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

No definition available.

Name:	nvsl_InterestBearingDepositLiabilitiesPercentage
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Data Type:	num:percentItemType
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Period Type:	instant

Percentage of interest-bearing domestic negotiable order of withdrawal (NOW) demand deposit liabilities.

No definition available.

Name:	nvsl_InterestBearingDomesticDepositNegotiableOrderOfWithdrawalNowPercentage
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Data Type:	num:percentItemType
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Percentage of interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity.

No definition available.

Name:	nvsl_InterestBearingDomesticDepositSavingsPercentage
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Data Type:	num:percentItemType
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The aggregate percentage of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

No definition available.

Name:	nvsl_NonInterestBearingDepositLiabilitiesPercentage
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Data Type:	num:percentItemType
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The amount of money in accounts that may bear interest and that the depositor is entitled to withdraw at any time without prior notice.

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 210.9-03.12)

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

Name:	us-gaap_DemandDepositAccounts
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

Name:	us-gaap_Deposits
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

Name:	us-gaap_DepositsMoneyMarketDeposits
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

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

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

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

- References

No definition available.

Name:	us-gaap_InterestBearingDepositLiabilitiesAbstract
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Data Type:	xbrli:stringItemType
Balance Type:	na
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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.