Incentive Plans (Details) - USD ($)				12 Months Ended
	Jan. 02, 2014	Feb. 13, 2013	Mar. 07, 2012	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2010	Nov. 30, 2010	May 03, 2005	Dec. 31, 1993
Stock Options
Incentive plans
Compensation expense				$ 994	$ 3,309
Unrecognized compensation related to unvested awards				$ 0
Options
Balance at the beginning of the period(in shares)				139,750
Granted (in shares)				0
Exercised (in shares)				(1,507)
Cancelled (in shares)				(100,493)
Balance at the end of the period (in shares)				37,750	139,750
Exercisable at the end of the period (in shares)				37,750
Weighted-Average Exercise Price Per Share
Outstanding at the beginning of the period (in dollars per share)				$ 6.66
Exercised (in dollars per share)				3.20
Cancelled (in dollars per share)				7.43
Outstanding at the end of the period (in dollars per share)				4.75	$ 6.66
Exercisable at the end of the period (in dollars per share)				$ 4.75
Weighted-Average Remaining Contractual Term
Outstanding at the end of the period				4 years 2 months 16 days
Exercisable at the end of the period				4 years 2 months 16 days
Aggregate Intrinsic Value
Outstanding at the end of the period				$ 10,005
Exercisable at the end of the period				10,005
Additional disclosures
Intrinsic value of options exercised				964	$ 8,166
Cash received from options exercised				$ 4,822	$ 10,666
Stock Options | Minimum
Incentive plans
Exercisable period				1 year
Stock Options | Maximum
Incentive plans
Expiration term				10 years
1993 Plan
Incentive plans
Number of common shares authorized									50,000
Purchase price as a percentage of market value				90.00%
Common shares issued				22,118	0
2003 Plan | Stock Options
Incentive plans
Number of shares eliminated								172,500
2005 Plan | Stock Options
Incentive plans
Shares available for grant				0				200,000
2005 Plan | Stock Options | Minimum
Incentive plans
Purchase price as a percentage of market value				100.00%
2010 Plan | Equity Appreciation Rights Plan
Incentive plans
Compensation income				$ 37,000	$ 69,000
Equity Appreciation Rights Plan
Vesting period from the base date				3 years
Shares issued (in units)						100,000
Shares granted (in units)	50,000	350,000	250,000	31,666	52,500
Accrued compensation included in other accrued liabilities				$ 23,000	$ 61,000
Accrued compensation included in other long-term liabilities				22,000	82,000
Accrued compensation liability
Beginning Balance				143,000	259,000
Reductions				(36,000)	(69,000)
Payments				(62,000)	(47,000)
Ending Balance				45,000	143,000
Accrued compensation liability
Compensation liability included in other accrued liabilities				23,000	61,000
Accrued compensation included in other long-term liabilities				$ 22,000	$ 82,000
2010 Plan | Equity Appreciation Rights Plan | Maximum
Incentive plans
Number of common shares authorized							1,000,000
Equity Appreciation Rights Plan
Redemption cash payment period				90 days