CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 02, 2016	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Jan. 02, 2016	Dec. 27, 2014	Dec. 28, 2013
Income Statement [Abstract]
Net sales	$ 478,960	$ 419,783	$ 413,359	$ 429,677	$ 453,522	$ 435,595	$ 429,738	$ 442,460	$ 1,741,779	$ 1,761,315	$ 1,588,702
Cost of sales									1,450,876	1,491,488	1,325,365
Selling, general and administrative expenses									186,749	196,343	186,435
Amortization of intangible assets									7,785	9,184	7,782
Restructuring and other charges									12,576	21,526	12,586
Impairment of intangible assets									0	0	24,493
Operating income	24,822	19,516	21,655	17,800	11,231	10,233	12,438	8,872	83,793	42,774	32,041
Gain on bargain purchase									0	0	(17,262)
Interest expense, net									100,805	106,661	112,579
Loss on early extinguishment of debt, net									1,252	27,449	11,324
Other income, net									(3,196)	(442)	(2,485)
Loss from continuing operations before income taxes									(15,068)	(90,894)	(72,115)
Income tax expense									4,393	4,159	14,161
Loss from continuing operations	(4,365)	(3,562)	(3,355)	(8,179)	(23,398)	(14,030)	(39,942)	(17,683)	(19,461)	(95,053)	(86,276)
(Loss) income from discontinued operations, net of taxes	(13,159)	319	950	500	4,899	3,137	1,305	1,849	(11,390)	11,190	17,490
Net loss	$ (17,524)	$ (3,243)	$ (2,405)	$ (7,679)	$ (18,499)	$ (10,893)	$ (38,637)	$ (15,834)	(30,851)	(83,863)	(68,786)
Other comprehensive (loss) income:
Changes in pension and other employee benefit accounts, net of taxes									(3,438)	(56,576)	31,430
Currency translation adjustment, net									(4,295)	(1,321)	(4,529)
Total other comprehensive (loss) income									(7,733)	(57,897)	26,901
Comprehensive loss									$ (38,584)	$ (141,760)	$ (41,885)
(Loss) income per share – basic:
Continuing operations per share - basic	$ (0.06)	$ (0.05)	$ (0.05)	$ (0.12)	$ (0.34)	$ (0.21)	$ (0.60)	$ (0.27)	$ (0.29)	$ (1.42)	$ (1.34)
Discontinued operations per share - basic	(0.20)	0.00	0.01	0.01	0.07	0.05	0.02	0.03	(0.16)	0.17	0.27
Net loss per share - basic	(0.26)	(0.05)	(0.04)	(0.11)	(0.27)	(0.16)	(0.58)	(0.24)	(0.45)	(1.25)	(1.07)
(Loss) income per share – diluted:
Continuing operations per share - diluted	(0.06)	(0.05)	(0.05)	(0.12)	(0.34)	(0.21)	(0.60)	(0.27)	(0.29)	(1.42)	(1.34)
Discontinued operations per share - diluted	(0.20)	0.00	0.01	0.01	0.07	0.05	0.02	0.03	(0.16)	0.17	0.27
Net loss per share - diluted	$ (0.26)	$ (0.05)	$ (0.04)	$ (0.11)	$ (0.27)	$ (0.16)	$ (0.58)	$ (0.24)	$ (0.45)	$ (1.25)	$ (1.07)
Weighted average shares outstanding:
Basic shares									67,832	66,952	64,576
Diluted shares									67,832	66,952	64,576