CONSOLIDATED STATEMENTS OF PARTNERS' CAPITAL - USD ($) shares in Thousands, $ in Thousands	Total	Common Unitholders [Member]	Accumulated Other Comprehensive (Loss) [Member]
Balance at Sep. 27, 2014	$ 1,021,453	$ 1,067,358	$ (45,905)
Balance (in units) at Sep. 27, 2014		60,317
Net income	84,352	$ 84,352
Net unrealized (losses) gains on cash flow hedges	(1,159)		(1,159)
Reclassification of realized losses on cash flow hedges into earnings	1,388		1,388
Amortization of net actuarial losses and prior service credits into earnings and net change in funded status of benefit plans	(5,207)		(5,207)
Recognition in earnings of net actuarial loss for pension settlement	2,000		2,000
Partnership distributions	(213,118)	$ (213,118)
Common Units issued under Restricted Unit Plans (in units)		214
Compensation cost recognized under Restricted Unit Plans, net of forfeitures	8,611	$ 8,611
Balance at Sep. 26, 2015	898,320	$ 947,203	(48,883)
Balance (in units) at Sep. 26, 2015		60,531
Net income	14,440	$ 14,440
Net unrealized (losses) gains on cash flow hedges	6		6
Reclassification of realized losses on cash flow hedges into earnings	1,100		1,100
Amortization of net actuarial losses and prior service credits into earnings and net change in funded status of benefit plans	(55)		(55)
Recognition in earnings of net actuarial loss for pension settlement	2,000		2,000
Partnership distributions	(215,522)	$ (215,522)
Common Units issued under Restricted Unit Plans (in units)		258
Compensation cost recognized under Restricted Unit Plans, net of forfeitures	7,942	$ 7,942
Balance at Sep. 24, 2016	708,231	$ 754,063	(45,832)
Balance (in units) at Sep. 24, 2016		60,789
Net income	37,995	$ 37,995
Net unrealized (losses) gains on cash flow hedges	(10)		(10)
Reclassification of realized losses on cash flow hedges into earnings	215		215
Amortization of net actuarial losses and prior service credits into earnings and net change in funded status of benefit plans	10,715		10,715
Recognition in earnings of net actuarial loss for pension settlement	6,100		6,100
Partnership distributions	(216,576)	$ (216,576)
Common Units issued under Restricted Unit Plans (in units)		316
Compensation cost recognized under Restricted Unit Plans, net of forfeitures	6,312	$ 6,312
Balance at Sep. 30, 2017	$ 552,982	$ 581,794	$ (28,812)
Balance (in units) at Sep. 30, 2017		61,105