Condensed Consolidating Schedules - Cash Flow (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2017	Oct. 02, 2016	Oct. 01, 2017	Oct. 02, 2016	Jan. 01, 2017
Condensed Financial Statements, Captions [Line Items]
Capital lease obligations, less current portion	$ 13,162		$ 13,162		$ 13,602
Capital lease obligations, current portion	571		571		467
Transaction and severance costs	128	$ 166	698	$ 1,349
Cash flows provided by (used in) operating activities:
Net Cash Provided by (Used in) Operating Activities			94,240	111,254
Cash flows provided by (used in) investing activities:
Proceeds from sale of property and equipment			(71,910)	(66,535)
Proceeds from Sale of Property, Plant, and Equipment			424	426
Payments to Develop Software			(2,520)	(8,788)
Net cash used in investing activities			(74,006)	(74,897)
Repayments on senior term loan			(5,700)	(5,700)
Repayments of Notes Payable			(13)	(37)
Cash flows from financing activities:
Repayments on note payable				(37)
Proceeds from sale leaseback transaction			4,073	0
Repayments of Long-term Capital Lease Obligations			(340)	(311)
Sale Leaseback Transaction, Payments, Financing Activities			(1,789)	(1,466)
Excess tax benefit realized from stock-based compensation			0	4
Adjustments to Additional Paid in Capital, Other			1,447	0
Net cash used in financing activities			(2,322)	(7,510)
Effect of foreign exchange rate changes on cash			492	356
Change in cash and cash equivalents			18,404	29,203
Cash and cash equivalents at beginning of period			61,023	50,654
Cash and cash equivalents at end of period	79,427	79,857	79,427	79,857
Guarantors
Condensed Financial Statements, Captions [Line Items]
Capital lease obligations, less current portion	0		0		0
Capital lease obligations, current portion	0		0		0
Transaction and severance costs	0	0	0	55
Cash flows provided by (used in) operating activities:
Net Cash Provided by (Used in) Operating Activities			24,632	17,674
Cash flows provided by (used in) investing activities:
Proceeds from sale of property and equipment			(21,407)	(15,506)
Proceeds from Sale of Property, Plant, and Equipment			0	0
Payments to Develop Software			(2,520)	(2,784)
Net cash used in investing activities			(23,927)	(18,290)
Repayments on senior term loan			0	0
Repayments of Notes Payable			(13)
Cash flows from financing activities:
Repayments on note payable				(37)
Proceeds from sale leaseback transaction			0
Repayments of Long-term Capital Lease Obligations			0	0
Sale Leaseback Transaction, Payments, Financing Activities			0	0
Excess tax benefit realized from stock-based compensation				0
Adjustments to Additional Paid in Capital, Other			0
Net cash used in financing activities			(13)	(37)
Effect of foreign exchange rate changes on cash			0	0
Change in cash and cash equivalents			692	(653)
Cash and cash equivalents at beginning of period			1,158	1,797
Cash and cash equivalents at end of period	1,850	1,144	1,850	1,144
Non-Guarantors
Condensed Financial Statements, Captions [Line Items]
Capital lease obligations, less current portion	57		57		60
Capital lease obligations, current portion	9		9		7
Transaction and severance costs	0	0	0	0
Cash flows provided by (used in) operating activities:
Net Cash Provided by (Used in) Operating Activities			1,040	240
Cash flows provided by (used in) investing activities:
Proceeds from sale of property and equipment			(768)	(206)
Proceeds from Sale of Property, Plant, and Equipment			0	0
Payments to Develop Software			0	0
Net cash used in investing activities			(768)	(206)
Repayments on senior term loan			0	0
Repayments of Notes Payable			0
Cash flows from financing activities:
Repayments on note payable				0
Proceeds from sale leaseback transaction			0
Repayments of Long-term Capital Lease Obligations			(5)	(3)
Sale Leaseback Transaction, Payments, Financing Activities			0	0
Excess tax benefit realized from stock-based compensation				0
Adjustments to Additional Paid in Capital, Other			0
Net cash used in financing activities			(5)	(3)
Effect of foreign exchange rate changes on cash			492	356
Change in cash and cash equivalents			759	387
Cash and cash equivalents at beginning of period			6,777	6,622
Cash and cash equivalents at end of period	7,536	7,009	7,536	7,009
Subsidiary Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Capital lease obligations, less current portion	13,105		13,105		13,542
Capital lease obligations, current portion	562		562		460
Transaction and severance costs	128	166
Cash flows from financing activities:
Cash and cash equivalents at beginning of period			53,088
Cash and cash equivalents at end of period	70,041		70,041
Issuer
Condensed Financial Statements, Captions [Line Items]
Transaction and severance costs			698	1,294
Cash flows provided by (used in) operating activities:
Net Cash Provided by (Used in) Operating Activities			68,568	93,340
Cash flows provided by (used in) investing activities:
Proceeds from sale of property and equipment			(49,735)	(50,823)
Proceeds from Sale of Property, Plant, and Equipment			424	426
Payments to Develop Software			0	(6,004)
Net cash used in investing activities			(49,311)	(56,401)
Repayments on senior term loan			(5,700)	(5,700)
Repayments of Notes Payable			0
Cash flows from financing activities:
Repayments on note payable				0
Proceeds from sale leaseback transaction			4,073
Repayments of Long-term Capital Lease Obligations			(335)	(308)
Sale Leaseback Transaction, Payments, Financing Activities			(1,789)	(1,466)
Excess tax benefit realized from stock-based compensation				4
Adjustments to Additional Paid in Capital, Other			1,447
Net cash used in financing activities			(2,304)	(7,470)
Effect of foreign exchange rate changes on cash			0	0
Change in cash and cash equivalents			16,953	29,469
Cash and cash equivalents at beginning of period			53,088	42,235
Cash and cash equivalents at end of period	70,041	71,704	70,041	71,704
Eliminations
Condensed Financial Statements, Captions [Line Items]
Capital lease obligations, less current portion	0		0		0
Capital lease obligations, current portion	0		0		$ 0
Transaction and severance costs	0	0	0	0
Cash flows provided by (used in) operating activities:
Net Cash Provided by (Used in) Operating Activities			0	0
Cash flows provided by (used in) investing activities:
Proceeds from sale of property and equipment			0	0
Proceeds from Sale of Property, Plant, and Equipment			0	0
Payments to Develop Software			0	0
Net cash used in investing activities			0	0
Repayments on senior term loan			0	0
Repayments of Notes Payable			0
Cash flows from financing activities:
Repayments on note payable				0
Proceeds from sale leaseback transaction			0
Repayments of Long-term Capital Lease Obligations			0	0
Sale Leaseback Transaction, Payments, Financing Activities			0	0
Excess tax benefit realized from stock-based compensation				0
Adjustments to Additional Paid in Capital, Other			0
Net cash used in financing activities			0	0
Effect of foreign exchange rate changes on cash			0	0
Change in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			0	0
Cash and cash equivalents at end of period	$ 0	$ 0	$ 0	$ 0