v2.4.0.8

Commitments and Contingencies (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 29, 2013 | Dec. 30, 2012 | Jan. 01, 2012
Commitments and Contingencies Disclosure [Abstract] |  |  |
Deferred rent credit related to leasehold improvements | $ 1.9 | $ 1.9 |
Assets Under Long Term Financing Obligation Net | 0.6 | 0.7 |
Accumulated Depreciation For Assets Under Long Term Financing Obligation | 0.3 | 0.3 |
Operating Leases, Rent Expense | $ 1.0 | $ 0.8 | $ 0.9

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- Definition Accumulated depreciation related to assets under long term financing obligation. + References No definition available. + Details
Name: | nile_AccumulatedDepreciationForAssetsUnderLongTermFinancingObligation
Namespace Prefix: | nile_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Assets under long term financing obligation net of accumulated depreciation. + References No definition available. + Details
Name: | nile_AssetsUnderLongTermFinancingObligationNet
Namespace Prefix: | nile_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Details
Name: | us-gaap_CommitmentsAndContingenciesDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e39896-112707 + Details
Name: | us-gaap_DeferredRentCredit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References No definition available. + Details
Name: | us-gaap_LeaseAndRentalExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration