Comprehensive Income Changes in AOCI by component (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 01, 2014	Mar. 02, 2013	Mar. 01, 2014	Mar. 02, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	$ 364	$ (4,168)	$ 849	$ (3,686)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]
OCI before reclassifications	2,234	2,621	2,385	2,620
Amounts reclassified from AOCI	(708)	(536)	(1,344)	(1,017)
Net current-period OCI	1,526	2,085	1,041	1,603
Balance at end of period	1,890	(2,083)	1,890	(2,083)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	364	(3,807)	1,000	(3,326)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]
OCI before reclassifications	2,234	2,676	2,234	2,676
Amounts reclassified from AOCI	(708)	(536)	1,344	1,017
Net current-period OCI	1,526	2,140	890	1,659
Balance at end of period	1,890	(1,667)	1,890	(1,667)
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	0	(361)	(151)	(360)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]
OCI before reclassifications	0	(55)	151	(56)
Amounts reclassified from AOCI	0	0	0	0
Net current-period OCI	0	(55)	151	(56)
Balance at end of period	$ 0	$ (416)	$ 0	$ (416)