Consolidated Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Parent [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]	Natural Gas Swap [Member]	Natural Gas Swap [Member] Parent [Member]	Natural Gas Swap [Member] AOCI Attributable to Parent [Member]	Corn Option [Member]	Corn Option [Member] Parent [Member]	Corn Option [Member] AOCI Attributable to Parent [Member]
Balance (in shares) at Jan. 03, 2015			164,712,663
Stockholders' Equity, Beginning Balance at Jan. 03, 2015	$ 2,051,134	$ 1,952,990	$ 1,662	$ 1,479,637	$ (23,207)	$ (177,060)	$ 671,958	$ 98,144
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	85,279	78,531					78,531	6,748
Distribution of noncontrolling interest earnings	(3,295)							(3,295)
Deductions to noncontrolling interests	(87)							(87)
Pension liability adjustments, net of tax	4,202	4,202				4,202
Total natural gas derivatives									$ 0			$ 1,767	$ 1,767	$ 1,767
Foreign currency translation adjustments	(162,436)	(164,827)				(164,827)		2,391
Issuance of non-vested stock (in shares)			261,615
Issuance of non-vested stock	3,791	3,791	$ 3	3,788
Stock-based compensation	2,083	2,083		2,083
Tax benefits associated with stock-based compensation	(389)	(389)		(389)
Treasury stock (in shares)			(834,477)
Treasury stock	(11,109)	(11,109)			(11,109)
Issuance of common stock (in shares)			595,575
Issuance of common stock	3,670	3,670	$ 6	3,664
Balance (in shares) at Jan. 02, 2016			164,735,376
Stockholders' Equity, Ending Balance at Jan. 02, 2016	1,974,610	1,870,709	$ 1,671	1,488,783	(34,316)	(335,918)	750,489	103,901
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	107,224	102,313					102,313	4,911
Distribution of noncontrolling interest earnings	(3,688)							(3,688)
Pension liability adjustments, net of tax	(1,016)	(1,016)				(1,016)
Total natural gas derivatives												625	625	625
Foreign currency translation adjustments	(5,593)	(3,697)				(3,697)		(1,896)
Issuance of non-vested stock (in shares)			341,185
Issuance of non-vested stock	4,131	4,131	$ 3	4,128
Stock-based compensation	4,081	4,081		4,081
Tax benefits associated with stock-based compensation	(364)	(364)		(364)
Treasury stock (in shares)			(693,250)
Treasury stock	(6,593)	(6,593)			(6,593)
Issuance of common stock (in shares)			229,247
Issuance of common stock	2,805	2,805	$ 2	2,803
Balance (in shares) at Dec. 31, 2016			164,612,558
Stockholders' Equity, Ending Balance at Dec. 31, 2016	2,076,222	1,972,994	$ 1,676	1,499,431	(40,909)	(340,006)	852,802	103,228
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adjustment to initially apply FASB ASC No. 2016-09 Improvements to Employee Share-Based Payment Accounting	(43)	(43)					(43)
Net income	133,354	128,468					128,468	4,886
Distribution of noncontrolling interest earnings	(4,020)							(4,020)
Deductions to noncontrolling interests	(19,112)	(1,721)		(1,721)				(17,391)
Pension liability adjustments, net of tax	5,829	5,829				5,829
Total natural gas derivatives									$ (18)	$ (18)	$ (18)	$ (1,078)	$ (1,078)	$ (1,078)
Foreign currency translation adjustments	121,810	125,749				125,749		(3,939)
Stock-based compensation	14,831	14,831		14,831
Treasury stock (in shares)			(210,206)
Treasury stock	(3,154)	(3,154)			(3,154)
Issuance of common stock (in shares)			251,085
Issuance of common stock	3,076	3,076	$ 3	3,073
Balance (in shares) at Dec. 30, 2017			164,653,437
Stockholders' Equity, Ending Balance at Dec. 30, 2017	$ 2,327,697	$ 2,244,933	$ 1,679	$ 1,515,614	$ (44,063)	$ (209,524)	$ 981,227	$ 82,764