Unit-Based Compensation Arrangements - Summary of Activity In the Restricted Units Plans (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares	12 Months Ended
	Sep. 30, 2017		Sep. 24, 2016		Sep. 26, 2015
Units [Rollforward]
Outstanding, beginning of period (in units)	654,120		627,399		694,927
Awarded (in units)	323,715		307,559		154,403
Forfeited (in units)	(6,737)		(12,057)		(7,607)
Vested (in units)	(350,053)	[1]	(268,781)	[1]	(214,324)
Outstanding, end of period (in units)	621,045		654,120		627,399
Weighted Average Grant Date Fair Value Per Unit [Abstract]
Outstanding, beginning of period (in dollars per unit)	$ 26.74		$ 31.87		$ 32.07
Awarded (in dollars per unit)	21.00		23.62		37.59
Forfeited (in dollars per unit)	(23.51)		(25.44)		(31.04)
Vested (in dollars per unit)	(29.74)	[1]	(35.19)	[1]	(36.68)
Outstanding, end of period (in dollars per unit)	$ 22.10		$ 26.74		$ 31.87

[1] During fiscal 2017 and 2016, the Partnership withheld 34,883 and 10,477, respectively, Common Units from participants for income tax withholding purposes for those executive officers of the Partnership whose shares of restricted units vested during the period.