Restructuring (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Nov. 27, 2011
Administrative Efficiency Restructuring Plan [Member]
Liabilities for various initiatives and changes
Balance at Aug 28, 2011	$ 10.6
Costs incurred and charged to expense	2.3
Costs paid or otherwise settled	(7.3)
Changes in estimates	(0.4)
Balance at November 27, 2011	5.2
2010 Plan [Member]
Liabilities for various initiatives and changes
Balance at Aug 28, 2011	1.3
Costs incurred and charged to expense	0.4
Costs paid or otherwise settled	(1.1)
Changes in estimates	(0.3)
Balance at November 27, 2011	0.3
Network Optimization Plan [Member]
Liabilities for various initiatives and changes
Balance at Aug 28, 2011	5.3
Costs incurred and charged to expense	3.4
Costs paid or otherwise settled	(2.8)
Changes in estimates	0.6
Balance at November 27, 2011	6.5
Severance and related costs [Member] | Administrative Efficiency Restructuring Plan [Member]
Liabilities for various initiatives and changes
Balance at Aug 28, 2011	8.2
Costs paid or otherwise settled	(2.7)
Changes in estimates	(0.4)
Balance at November 27, 2011	5.1
Severance and related costs [Member] | 2010 Plan [Member]
Liabilities for various initiatives and changes
Balance at Aug 28, 2011	1.2
Costs paid or otherwise settled	(0.6)
Changes in estimates	(0.3)
Balance at November 27, 2011	0.3
Severance and related costs [Member] | Network Optimization Plan [Member]
Liabilities for various initiatives and changes
Balance at Aug 28, 2011	5.2
Costs incurred and charged to expense	0.8
Costs paid or otherwise settled	(0.7)
Changes in estimates	0.6
Balance at November 27, 2011	5.9
Plan implementation costs [Member] | Administrative Efficiency Restructuring Plan [Member]
Liabilities for various initiatives and changes
Balance at Aug 28, 2011	2.4
Costs incurred and charged to expense	2.3
Costs paid or otherwise settled	(4.6)
Balance at November 27, 2011	0.1
Plan implementation costs [Member] | 2010 Plan [Member]
Liabilities for various initiatives and changes
Balance at Aug 28, 2011	0.1
Costs incurred and charged to expense	0.4
Costs paid or otherwise settled	(0.5)
Plan implementation costs [Member] | Network Optimization Plan [Member]
Liabilities for various initiatives and changes
Balance at Aug 28, 2011	0.1
Costs incurred and charged to expense	2.6
Costs paid or otherwise settled	(2.1)
Changes in estimates	0.6
Balance at November 27, 2011	$ 0.6