Real Estate Debt Investments (Details) (USD $)	6 Months Ended
Jun. 30, 2013
Mortgage Loans on Real Estate [Line Items]
Carrying Amount	$ 2,500,000
Investment face amount	11,250,000
Description of variable rate basis	LIBOR
LIBOR floor	1.00%
Coupon	8.00%
First mortgage loan
Mortgage Loans on Real Estate [Line Items]
Number	1
Maturity Date	2016-03
Extended Maturity Date	2018-03
Principal Amount	2,500,000
Carrying Amount	$ 2,500,000
Spread over LIBOR	7.00%
Unleveraged Current Yield	8.08%

Additional participation interest in loan investment.

No definition available.

Name:	nshi_InvestmentFaceAmount
Namespace Prefix:	nshi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the percentage of current yield on real estate mortgage loans.

+ References

No definition available.

+ Details

Name:	nshi_MortgageLoansOnRealEstateCurrentYieldPercentage
Namespace Prefix:	nshi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The extended maturity date of the investment.

+ References

No definition available.

+ Details

Name:	nshi_MortgageLoansOnRealEstateExtendedMaturities
Namespace Prefix:	nshi_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

- Definition

The maturity date of the investment.

+ References

No definition available.

+ Details

Name:	nshi_MortgageLoansOnRealEstateMaturities
Namespace Prefix:	nshi_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the floor for the variable rate base of the mortgage loans on real estate.

+ References

No definition available.

+ Details

Name:	nshi_MortgageLoansOnRealEstateVariableRateBasisFloor
Namespace Prefix:	nshi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin.

+ References

No definition available.

+ Details

Name:	us-gaap_LoansReceivableBasisSpreadOnVariableRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The reference rate for the variable rate of the loans receivable, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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

- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(c))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph c

-Article 7

+ Details

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

- Definition

Amount of the contractual principal due at the origination of the mortgage loan (face amount).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 29

-Article 12

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

+ Details

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

- Definition

The stated interest rate on the mortgage loan receivable or the weighted average interest rate on a group of loans.

+ References

+ Details

Name:	us-gaap_MortgageLoansOnRealEstateInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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

- Definition

Indicates the number of mortgages under each classification.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29.3)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 29

-Paragraph 3

-Article 12

+ Details

Name:	us-gaap_MortgageLoansOnRealEstateNumberOfLoans
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration