Income Taxes - Deferred Tax Assets (Liabilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017
Deferred tax assets
Accrued liabilities	$ 16,339	$ 11,378
Accrued bonuses	724	192
Other assets and liabilities	10,705	7,913
Equity awards	5,862	5,690
Other	2,196	2,178
Foreign net operating losses	1,555	2,773
Foreign tax credit carryforwards	7,230	4,707
Total deferred tax assets	44,611	34,831
Valuation allowance on foreign net operating and capital losses, foreign deferred tax assets, and foreign tax credit carryforwards	(8,183)	(7,415)
Total deferred tax assets, net of valuation allowances	36,428	27,416
Deferred tax liabilities
Deferred expenses	(5,576)	(6,912)
Accelerated depreciation	(24,239)	(19,228)
Goodwill	(12,645)	(12,248)
Other	(1,064)	(989)
Total deferred tax liabilities	(43,524)	(39,377)
Net deferred liability	$ (7,096)	(11,961)
Other tax disclosures
Expiration term of foreign tax credit carryforwards	10 years
Foreign tax authority
Other tax disclosures
Net operating loss carryovers	$ 5,300	9,400
Valuation allowance related to net operating losses	600	$ 2,100
Foreign tax credit carryforwards
Deferred tax assets
Valuation allowance on foreign net operating and capital losses, foreign deferred tax assets, and foreign tax credit carryforwards	$ (7,200)