Note 11 - Associate Benefits (Detail) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Defined Contribution Plan, Employer Matching Contribution, Percent	25.00%
Defined Contribution Plan Maximum Percentage of Annual Contribution Employee Subject to Match	6.00%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage	20.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount (in Dollars)	$ 236,000	$ 182,000	$ 168,000

Maximum percentage of employee gross pay, by the terms of the plan, that the employer may apply a percentage match contribution to a defined contribution plan.

No definition available.

Name:	nrci_DefinedContributionPlanMaximumPercentageOfAnnualContributionEmployeeSubjectToMatch
Namespace Prefix:	nrci_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration