Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of period	$ 3,119	$ 3,288	$ 1,882
Additions for tax positions taken in the current year	1,677	74	214
Increases for tax positions taken in prior years	16	1,479	1,581
Decreases for tax positions taken in prior years	(390)	(964)	(184)
Settlement with tax authorities	(32)	(558)
Settlement with tax authorities			79
Expiration of statute of limitations	(537)	(200)	(284)
Balance at end of period	$ 3,853	$ 3,119	$ 3,288