Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 26, 2015	Dec. 27, 2014
Change in fair value of plan assets [Roll Forward]
Defined benefit plan, amortization of net gains (losses) expected to be recognized in next fiscal year	$ (2,200)
Defined benefit plan, amortization of prior service credit expected to be recognized in next fiscal year	$ (900)
Payable maximum period to be considered current	12 months
Funded status of the plans recognized [Abstract]
Long-term liability	$ (14,890)	$ (17,449)
Weighted average assumptions in net periodic benefit calculations [Abstract]
Ultimate health care cost trend rate	3.00%
Minimum [Member]
Weighted average assumptions in net periodic benefit calculations [Abstract]
Annual assumed rate of increase in the per capita cost of covered benefits	6.80%
Maximum [Member]
Weighted average assumptions in net periodic benefit calculations [Abstract]
Annual assumed rate of increase in the per capita cost of covered benefits	8.30%
Pension Benefits [Member]
Change in benefit obligation [Roll Forward]
Obligation at beginning of year	$ 192,761	207,738
Service cost	532	803	$ 973
Interest cost	7,553	8,032	8,590
Actuarial loss (gain)	9,399	(9,163)
Plan amendments	0	0
Business acquisitions	0	0
Benefit payments	(17,572)	(10,795)
Foreign currency translation adjustment	(13,937)	(3,854)
Obligation at end of year	178,736	192,761	207,738
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets at beginning of year	176,077	190,016
Actual return on plan assets	19,319	(1,682)
Employer contributions	2,377	1,513
Benefit payments	(17,572)	(10,795)
Foreign currency translation adjustment	(11,061)	(2,975)
Fair value of plan assets at end of year	169,140	176,077	190,016
Underfunded status at end of year	(9,596)	(16,684)
Incremental benefit payments	(7,000)
Unrecognized net actuarial loss	39,986	48,681
Unrecognized prior service credit	0	0
Funded status of the plans recognized [Abstract]
Long-term asset	4,442	765
Current liability	0	0
Long-term liability	(14,038)	(17,449)
Total underfunded status	(9,596)	(16,684)
Components of net periodic benefit cost [Abstract]
Service cost	532	803	973
Interest cost	7,553	8,032	8,590
Expected return on plan assets	(9,615)	(10,289)	(13,669)
Amortization of prior service (credit) cost	0	0	1
Amortization of net (gain) loss	2,898	2,710	752
Settlement charge	1,214	0	0
Net periodic benefit (income) cost	$ 2,582	$ 1,256	$ (3,353)
Weighted average assumptions in benefit obligations calculations [Abstract]
Discount rate	3.61%	4.02%
Expected long-term return on plan assets	5.56%	5.59%
Rate of inflation	3.30%	3.20%
Weighted average assumptions in net periodic benefit calculations [Abstract]
Discount rate	4.02%	4.03%	4.82%
Expected long-term return on plan assets	5.59%	5.58%	7.40%
Rate of inflation	3.20%	3.10%	3.40%
Other Benefits [Member]
Change in benefit obligation [Roll Forward]
Obligation at beginning of year	$ 15,843	$ 19,307
Service cost	232	363	$ 348
Interest cost	594	1,005	685
Actuarial loss (gain)	(249)	270
Plan amendments	43	(9,094)
Business acquisitions	0	5,655
Benefit payments	(1,023)	(1,037)
Foreign currency translation adjustment	(166)	(626)
Obligation at end of year	15,274	15,843	19,307
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Actual return on plan assets	0	0
Employer contributions	1,023	1,037
Benefit payments	(1,023)	(1,037)
Foreign currency translation adjustment	0	0
Fair value of plan assets at end of year	0	0	0
Underfunded status at end of year	(15,274)	(15,843)
Unrecognized net actuarial loss	614	767
Unrecognized prior service credit	(8,180)	(9,087)
Funded status of the plans recognized [Abstract]
Long-term asset	0	0
Current liability	(1,128)	(1,221)
Long-term liability	(14,146)	(14,622)
Total underfunded status	(15,274)	(15,843)
Components of net periodic benefit cost [Abstract]
Service cost	232	363	348
Interest cost	594	1,005	685
Amortization of prior service (credit) cost	(896)	6	6
Amortization of net (gain) loss	(60)	(28)	(218)
Net periodic benefit (income) cost	$ (130)	$ 1,346	$ 821
Weighted average assumptions in benefit obligations calculations [Abstract]
Discount rate	4.21%	4.25%
Rate of compensation increases	5.00%	5.00%
Weighted average assumptions in net periodic benefit calculations [Abstract]
Discount rate	4.25%	4.33%	4.89%
Rate of compensation increases	5.00%	5.00%	5.50%
U.K Plan [Member]
Change in fair value of plan assets [Roll Forward]
Percent of above benefit obligation on company sponsored UK pension plan	42.00%	41.00%
Percent above plan assets on company sponsored UK pension plan	36.00%	35.00%