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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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Valuation Charges (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Apr. 27, 2014	Apr. 26, 2015	Apr. 27, 2014	Apr. 28, 2013
Impairment charges related to goodwill
Property and equipment, net impairment charges		$ 9,000us-gaap_TangibleAssetImpairmentCharges	$ 16,122us-gaap_TangibleAssetImpairmentCharges
Intangible asset impairment charge			12,153
Goodwill impairment charges	133,825us-gaap_GoodwillImpairmentLoss		133,825us-gaap_GoodwillImpairmentLoss	50,100us-gaap_GoodwillImpairmentLoss
Total impairment valuation charges		9,000us-gaap_AssetImpairmentCharges	162,100us-gaap_AssetImpairmentCharges	50,100us-gaap_AssetImpairmentCharges
Remaining goodwill balance by property	108,970us-gaap_Goodwill	108,970us-gaap_Goodwill	108,970us-gaap_Goodwill	280,803us-gaap_Goodwill
Bettendorf
Impairment charges related to goodwill
Goodwill impairment charges	60,000		60,000
Remaining goodwill balance by property		5,713
Lake Charles
Impairment charges related to goodwill
Goodwill impairment charges	24,238		24,238
Lula, Mississippi
Impairment charges related to goodwill
Goodwill impairment charges	36,000		36,000	34,100
Remaining goodwill balance by property		6,581
Natchez, Mississippi
Impairment charges related to goodwill
Property and equipment, net impairment charges			1,922
Goodwill impairment charges	8,587		8,587	16,000
Total impairment valuation charges	28,275
Vicksburg, Mississippi
Impairment charges related to goodwill
Goodwill impairment charges	5,000		5,000
Remaining goodwill balance by property		27,167
Blackhawk
Impairment charges related to goodwill
Remaining goodwill balance by property		30,533
Boonville
Impairment charges related to goodwill
Remaining goodwill balance by property		2,599
Kansas City
Impairment charges related to goodwill
Remaining goodwill balance by property		7,182
Marquette
Impairment charges related to goodwill
Remaining goodwill balance by property		29,195
Nemacolin
Impairment charges related to goodwill
Property and equipment, net impairment charges		9,000	14,200
Intangible asset impairment charge			$ 12,153