CONSOLIDATED STATEMENTS OF PARTNERS' CAPITAL - USD ($) shares in Thousands, $ in Thousands	Total	Common Unitholders [Member]	Accumulated Other Comprehensive (Loss) [Member]
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 (loss) 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	(974)	$ (974)
Common Units issued under Restricted Unit Plans (in units)		316
Compensation costs recognized under Restricted Unit Plans	7,286	$ 7,286
Balance at Sep. 30, 2017	552,982	$ 581,794	(28,812)
Balance (in units) at Sep. 30, 2017		61,105
Net income	76,534	$ 76,534
Amortization of net actuarial losses and prior service credits into earnings and net change in funded status of benefit plans	4,142		4,142
Recognition in earnings of net actuarial loss for pension settlement	0
Partnership distributions	(147,185)	(147,185)
Common Units issued under Restricted Unit Plans	(847)	$ (847)
Common Units issued under Restricted Unit Plans (in units)		300
Compensation costs recognized under Restricted Unit Plans	8,198	$ 8,198
Balance at Sep. 29, 2018	493,824	$ 518,494	(24,670)
Balance (in units) at Sep. 29, 2018		61,405
Net income	68,632	$ 68,632
Amortization of net actuarial losses and prior service credits into earnings and net change in funded status of benefit plans	(1,516)		(1,516)
Recognition in earnings of net actuarial loss for pension settlement	0
Partnership distributions	(147,882)	(147,882)
Common Units issued under Restricted Unit Plans	(1,349)	$ (1,349)
Common Units issued under Restricted Unit Plans (in units)		261
Common Units issued for acquisition of business	1,600	$ 1,600
Common Units issued for acquisition of business (in units)		69
Compensation costs recognized under Restricted Unit Plans	10,521	$ 10,521
Balance at Sep. 28, 2019	$ 423,830	$ 450,016	$ (26,186)
Balance (in units) at Sep. 28, 2019		61,735