12.	Pension Plans and Other Postretirement Benefits

The following table provides the components of net periodic benefit costs:

	Pension Benefits
	Three Months Ended						Nine Months Ended
	June 24,			June 25,			June 24,			June 25,
	2017			2016			2017			2016
Interest cost	$	1,041		$	1,260		$	3,123		$	3,781
Expected return on plan assets		(537	)		(854	)		(1,611	)		(2,563	)
Amortization of net loss (gain)		1,301			1,304			3,901			3,913
Net periodic benefit cost	$	1,805		$	1,710		$	5,413		$	5,131

	Postretirement Benefits
	Three Months Ended						Nine Months Ended
	June 24,			June 25,			June 24,			June 25,
	2017			2016			2017			2016
Interest cost	$	96		$	130		$	288		$	400
Amortization of prior service credits		—			(100	)		—			(300	)
Amortization of net loss (gain)		(98	)		(74	)		(292	)		(223	)
Net periodic benefit cost	$	(2	)	$	(44	)	$	(4	)	$	(123	)

The Partnership expects to contribute approximately $9,527 to the defined benefit pension plan during fiscal 2017, of which $7,542 was contributed during the nine months ended June 24, 2017. The projected annual contribution requirements related to the Partnership’s postretirement health care and life insurance benefit plan for fiscal 2017 is $922, of which $899 was contributed during the nine months ended June 24, 2017.

The Partnership contributes to multi-employer pension plans (“MEPPs”) in accordance with various collective bargaining agreements covering union employees. As one of the many participating employers in these MEPPs, the Partnership is responsible with the other participating employers for any plan underfunding. As of June 24, 2017 and September 24, 2016, the Partnership’s estimated obligation to these MEPPs was $22,960 and $24,205, respectively, as a result of its voluntary withdrawal from certain MEPPs.