Stockholders' Equity - Stock Option Activity (Details) - Equity Incentive Plan $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 29, 2018 USD ($) $ / shares shares
Options Outstanding
Outstanding, beginning of period (In shares) | shares	659,334
Options exercised (In shares) | shares	(105,610)
Outstanding, end of period (In shares) | shares	553,724
Exercisable (In shares) | shares	430,104
Weighted Average Exercise Price
Outstanding, beginning of period (In dollars per share) | $ / shares	$ 8.12
Options exercised (In dollars per share) | $ / shares	9.93
Outstanding, end of period (In dollars per share) | $ / shares	7.77
Exercisable (In dollars per share) | $ / shares	$ 7.67
Additional Disclosures
Outstanding, weighted average remaining contractual life	3 years 6 months 22 days
Exercisable, weighted average remaining contractual life	3 years 6 months 16 days
Outstanding, aggregate intrinsic value | $	$ 3,308,931
Exercisable, aggregate intrinsic value | $	$ 2,620,928