Stockholders' Equity (Details 2) (Subsequent event) In Millions, unless otherwise specified	May 13, 2013
Subsequent event
Stockholders' Equity
Shares remaining available for sale under DRP	8.3

Represents the number of shares remaining available for sale under the dividend reinvestment plan.

No definition available.

Name:	nsre_CommonStockSharesRemainingAvailableForSalePursuantToDistributionReinvestmentPlan
Namespace Prefix:	nsre_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant