Restructuring (Details) $ in Thousands	12 Months Ended
Dec. 30, 2018 USD ($) employees	Dec. 31, 2017 USD ($)	Jan. 01, 2017 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 17,497	$ 21,045	$ 207,190
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	3,886
Charges (Benefits)	17,497	21,045	207,190
(Payments) Recoveries	(15,073)
Restructuring reserve, end	6,310	3,886
February 2018 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	0
Charges (Benefits)	12,387	0	0
(Payments) Recoveries	(6,938)
Restructuring reserve, end	5,449	0
December 2016 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	1,916
Charges (Benefits)	2,194	20,321	172,511
(Payments) Recoveries	(4,110)
Restructuring reserve, end	0	1,916
Restructuring and related cost, cost incurred to date	195,000
August 2016 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	1,774
Charges (Benefits)	2,919	749	34,438
(Payments) Recoveries	(4,018)
Restructuring reserve, end	675	1,774
Restructuring and related cost, cost incurred to date	38,100
Legacy Restructuring Plans
Restructuring Reserve [Roll Forward]
Restructuring and related cost, cost incurred to date	143,700
November 2014 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	196
Charges (Benefits)	(3)	(25)	241
(Payments) Recoveries	(7)
Restructuring reserve, end	186	196
Non-cash impairment charges \| December 2016 Plan
Restructuring Reserve [Roll Forward]
Charges (Benefits)	0	147	148,791
Non-cash impairment charges \| August 2016 Plan
Restructuring Reserve [Roll Forward]
Charges (Benefits)	0	0	17,926
Non-cash impairment charges \| November 2014 Plan
Restructuring Reserve [Roll Forward]
Charges (Benefits)	0	0	0
Employee Severance \| February 2018 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	0
Charges (Benefits)	12,130	0	0
(Payments) Recoveries	(6,681)
Restructuring reserve, end	5,449	0
Employee Severance \| December 2016 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	1,862
Charges (Benefits)	(799)	5,643	15,901
(Payments) Recoveries	(1,063)
Restructuring reserve, end	0	1,862
Employee Severance \| August 2016 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	1,735
Charges (Benefits)	2,665	(242)	15,591
(Payments) Recoveries	(3,788)
Restructuring reserve, end	612	1,735
Employee Severance \| November 2014 Plan
Restructuring Reserve [Roll Forward]
Charges (Benefits)	0	14	350
Facility Closing \| December 2016 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	0
Charges (Benefits)	6	707	0
(Payments) Recoveries	(6)
Restructuring reserve, end	0	0
Facility Closing \| August 2016 Plan
Restructuring Reserve [Roll Forward]
Charges (Benefits)	0	2	557
Facility Closing \| November 2014 Plan
Restructuring Reserve [Roll Forward]
Charges (Benefits)	0	0	(171)
Other Restructuring \| February 2018 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	0
Charges (Benefits)	257	0	0
(Payments) Recoveries	(257)
Restructuring reserve, end	0	0
Other Restructuring \| December 2016 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	54
Charges (Benefits)	2,987	13,824	7,819
(Payments) Recoveries	(3,041)
Restructuring reserve, end	0	54
Other Restructuring \| August 2016 Plan
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	39
Charges (Benefits)	254	989	364
(Payments) Recoveries	(230)
Restructuring reserve, end	63	39
Other Restructuring \| November 2014 Plan
Restructuring Reserve [Roll Forward]
Charges (Benefits)	(3)	$ (39)	$ 62
Minimum
Restructuring Reserve [Roll Forward]
(Payments) Recoveries	$ (12,000)
Minimum \| February 2018 Plan
Restructuring Cost and Reserve [Line Items]
Reorganization, number of jobs affected \| employees	150
Restructuring charges	$ 20,000
Severance costs	11,000
Facility costs	9,000
Maximum
Restructuring Reserve [Roll Forward]
(Payments) Recoveries	$ (20,000)
Maximum \| February 2018 Plan
Restructuring Cost and Reserve [Line Items]
Reorganization, number of jobs affected \| employees	250
Restructuring charges	$ 30,000
Severance costs	16,000
Facility costs	$ 14,000

Facility expenses incurred related to gas and oil produced and sold during the reporting period.

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