Stockholders' Equity - Additional Information (Details) - USD ($)		12 Months Ended
	Sep. 09, 2015	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015	Dec. 31, 2011	Dec. 30, 2016	Aug. 31, 2016	Aug. 31, 2015	Jul. 31, 2014	Feb. 28, 2013	Feb. 28, 2012
Exercisable period		3 years 7 months 28 days
Repurchase of shares		843,785
Shares reserved		975,903
Weighted-average grant date fair value of the options granted		$ 5.06	$ 3.95	$ 4.02
Total intrinsic value of options exercised		$ 800,000	$ 1,500,000	$ 1,900,000
Total unrecognized compensation cost related to non-vested share-based compensation arrangements		$ 3,300,000
Cost is expected to be recognized over a weighted average period		2 years 6 months 7 days
Excess tax benefits from stock-based awards		$ 0	$ 0	$ 36,000
Unvested restricted stock awarded		286,294	227,905	62,225
Stock repurchase program authorized amount		$ 6,700,000							$ 3,000,000	$ 3,000,000	$ 4,000,000
Remaining common stock value authorized to purchase under stock repurchase program lapsed							$ 1,000,000
Stock repurchase program additional amount authorized								$ 2,000,000
Stock repurchase, shares		6,544	199,776	562,440
Shares repurchased price, per share		$ 9.00	$ 7.92	$ 8.29
Cash paid in exchange to cancel vested stock options to be exercised			$ 275,000
Number of shares, vested stock options to be exercised, canceled		66,707	174,870	27,957
James H. Mackaness
Cash paid in exchange to cancel vested stock options to be exercised	$ 275,000
Number of shares, vested stock options to be exercised, canceled	92,656
Restricted Stock Units (RSUs)
Grant of non-qualified stock option					$ 20,000
The intrinsic value of the restricted stock units						$ 14.06
Number of shares, vested		30,789	209,193	46,759
Restricted stock units released, intrinsic value		$ 400,000
Restricted stock units released, Shares withheld		7,507
Restricted stock units released, value withheld		$ 100,000
Unvested restricted stock awarded		285,005	225,392	59,780
Weighted-average grant date fair value of restricted stock awarded		$ 11.89	$ 8.66	$ 9.76
Restricted Stock Units (RSUs) | Accelerated Vesting
Number of shares, vested		6,400
1998 Stock Plan
Voting rights on outstanding capital stock		10.00%
Exercise price of option		110.00%
Term of incentive stock options for major stock holders		5 years
Exercisable period		4 years
Maximum term of incentive stock options granted		10 years
Repurchase of shares		0	0
Expiration date of option Plan		2008-02
2008 Equity Incentive Plan
Grant of non-qualified stock option		300,000
Performance Award | Restricted Stock Units (RSUs)
Unvested restricted stock awarded		256,138
Weighted-average grant date fair value of restricted stock awarded		$ 11.40
Performance Award | Restricted Stock Units (RSUs) | Accelerated Vesting
Number of shares, vested		10,000
Performance Award | Restricted Stock Units (RSUs) | Accelerated Vesting | General and administrative
Stock-based compensation expense		$ 220,000