Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	Apr. 26, 2014	Jul. 27, 2013
Credit Agreement, December 3, 2012, Maturing December 2017 | Revolving Credit Facility | Standby Letters of Credit
Loss Contingencies [Line Items]
Letters of credit outstanding amount	$ 49.6
Prior Credit Agreement Which Has Been Terminated or Replaced | Revolving Credit Facility | Standby Letters of Credit
Loss Contingencies [Line Items]
Letters of credit outstanding amount		46.7
Performance Guarantee and Surety Bond
Loss Contingencies [Line Items]
Outstanding performance and other surety contract bonds	$ 415.7	$ 446.5