Supplemental Consolidating Financial Statements - Cash Flows (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended		12 Months Ended
	Apr. 26, 2014	Apr. 27, 2013	Jul. 27, 2013
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	$ 97,491	$ 91,327
Payments to Acquire Businesses, Net of Cash Acquired	(700)	(318,984)
INVESTING ACTIVITIES:
Capital expenditures	(70,585)	(45,743)
Proceeds from sale of assets	9,425	4,467
Return of capital from subsidiaries	0	0
Investment in subsidiaries	0	0
Changes in restricted cash	(305)	(31)
Net cash used in investing activities	(62,165)	(360,291)
FINANCING ACTIVITIES:
Proceeds from borrowings on Credit Agreement	337,000	310,500
Proceeds from Issuance of Senior Long-term Debt	0	93,825
Proceeds from issuance of long-term debt	0	125,000
Principal payments on Senior Credit Agreement	(375,469)	(276,063)
Debt Issuance Cost	0	(6,739)
Repurchases of common stock	(9,999)	(15,203)	(15,203)
Exercise of stock options and other	14,010	3,511
Restricted stock tax withholdings	(3,590)	(885)
Excess tax benefit from share-based awards	2,837	758
Principal payments on capital lease obligations	0	(74)
Intercompany funding	0	0
Net cash provided by financing activities	(35,211)	234,630
Net (decrease) increase in cash and equivalents	115	(34,334)
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	18,607	52,581	52,581
CASH AND EQUIVALENTS AT END OF PERIOD	18,722	18,247	18,607
Parent
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	2,007	1,715
Payments to Acquire Businesses, Net of Cash Acquired	0	0
INVESTING ACTIVITIES:
Capital expenditures	(6,901)	(6,992)
Proceeds from sale of assets	0	0
Return of capital from subsidiaries	0	0
Investment in subsidiaries	0	0
Changes in restricted cash	(305)	(31)
Net cash used in investing activities	(7,206)	(7,023)
FINANCING ACTIVITIES:
Proceeds from borrowings on Credit Agreement	337,000	310,500
Proceeds from Issuance of Senior Long-term Debt		0
Proceeds from issuance of long-term debt		125,000
Principal payments on Senior Credit Agreement	(375,469)	(276,063)
Debt Issuance Cost		(4,158)
Repurchases of common stock	(9,999)	(15,203)
Exercise of stock options and other	14,010	3,511
Restricted stock tax withholdings	(3,590)	(885)
Excess tax benefit from share-based awards	2,837	758
Principal payments on capital lease obligations		0
Intercompany funding	40,410	(138,152)
Net cash provided by financing activities	5,199	5,308
Net (decrease) increase in cash and equivalents	0	0
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	0	0	0
CASH AND EQUIVALENTS AT END OF PERIOD	0	0
Issuer
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	(4,261)	(2,198)
Payments to Acquire Businesses, Net of Cash Acquired	0	0
INVESTING ACTIVITIES:
Capital expenditures	0	0
Proceeds from sale of assets	0	0
Return of capital from subsidiaries	683	1,816
Investment in subsidiaries	(4,635)	(400)
Changes in restricted cash	0	0
Net cash used in investing activities	(3,952)	1,416
FINANCING ACTIVITIES:
Proceeds from borrowings on Credit Agreement	0	0
Proceeds from Issuance of Senior Long-term Debt		93,825
Proceeds from issuance of long-term debt		0
Principal payments on Senior Credit Agreement	0	0
Debt Issuance Cost		(2,581)
Repurchases of common stock	0	0
Exercise of stock options and other	0	0
Restricted stock tax withholdings	0	0
Excess tax benefit from share-based awards	0	0
Principal payments on capital lease obligations		0
Intercompany funding	8,213	(90,462)
Net cash provided by financing activities	8,213	782
Net (decrease) increase in cash and equivalents	0	0
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	0	0	0
CASH AND EQUIVALENTS AT END OF PERIOD	0	0
Subsidiary Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	102,153	93,601
Payments to Acquire Businesses, Net of Cash Acquired	0	(318,984)
INVESTING ACTIVITIES:
Capital expenditures	(59,504)	(35,165)
Proceeds from sale of assets	7,813	4,412
Return of capital from subsidiaries	0	0
Investment in subsidiaries	(185)	0
Changes in restricted cash	0	0
Net cash used in investing activities	(51,876)	(349,737)
FINANCING ACTIVITIES:
Proceeds from borrowings on Credit Agreement	0	0
Proceeds from Issuance of Senior Long-term Debt		0
Proceeds from issuance of long-term debt		0
Principal payments on Senior Credit Agreement	0	0
Debt Issuance Cost		0
Repurchases of common stock	0	0
Exercise of stock options and other	0	0
Restricted stock tax withholdings	0	0
Excess tax benefit from share-based awards	0	0
Principal payments on capital lease obligations		(74)
Intercompany funding	(50,434)	222,278
Net cash provided by financing activities	(50,434)	222,204
Net (decrease) increase in cash and equivalents	(157)	(33,932)
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	18,166	51,563	51,563
CASH AND EQUIVALENTS AT END OF PERIOD	18,009	17,631
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	(2,408)	(1,791)
Payments to Acquire Businesses, Net of Cash Acquired	(700)	0
INVESTING ACTIVITIES:
Capital expenditures	(4,180)	(3,586)
Proceeds from sale of assets	1,612	55
Return of capital from subsidiaries	0	0
Investment in subsidiaries	0	0
Changes in restricted cash	0	0
Net cash used in investing activities	(3,268)	(3,531)
FINANCING ACTIVITIES:
Proceeds from borrowings on Credit Agreement	0	0
Proceeds from Issuance of Senior Long-term Debt		0
Proceeds from issuance of long-term debt		0
Principal payments on Senior Credit Agreement	0	0
Debt Issuance Cost		0
Repurchases of common stock	0	0
Exercise of stock options and other	0	0
Restricted stock tax withholdings	0	0
Excess tax benefit from share-based awards	0	0
Principal payments on capital lease obligations		0
Intercompany funding	5,948	4,920
Net cash provided by financing activities	5,948	4,920
Net (decrease) increase in cash and equivalents	272	(402)
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	441	1,018	1,018
CASH AND EQUIVALENTS AT END OF PERIOD	713	616
Eliminations and Reclassifications
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	0	0
Payments to Acquire Businesses, Net of Cash Acquired	0	0
INVESTING ACTIVITIES:
Capital expenditures	0	0
Proceeds from sale of assets	0	0
Return of capital from subsidiaries	(683)	(1,816)
Investment in subsidiaries	4,820	400
Changes in restricted cash	0	0
Net cash used in investing activities	4,137	(1,416)
FINANCING ACTIVITIES:
Proceeds from borrowings on Credit Agreement	0	0
Proceeds from Issuance of Senior Long-term Debt		0
Proceeds from issuance of long-term debt		0
Principal payments on Senior Credit Agreement	0	0
Debt Issuance Cost		0
Repurchases of common stock	0	0
Exercise of stock options and other	0	0
Restricted stock tax withholdings	0	0
Excess tax benefit from share-based awards	0	0
Principal payments on capital lease obligations		0
Intercompany funding	(4,137)	1,416
Net cash provided by financing activities	(4,137)	1,416
Net (decrease) increase in cash and equivalents	0	0
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	0	0	0
CASH AND EQUIVALENTS AT END OF PERIOD	$ 0	$ 0