v2.4.0.8

Preferred Stock (Details) | Dec. 29, 2013
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Preferred Stock [Abstract] |
Undesignated preferred stock authorized for future issuance | 5,000,000

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- Details
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Namespace Prefix: | nile_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Aggregate number of nonredeemable preferred shares reserved for future issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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Balance Type: | na
Period Type: | instant