Shareholders' Equity (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended
	Jun. 21, 2011	Sep. 29, 2012 Stock options	Sep. 24, 2011 Stock options	Sep. 29, 2012 Stock options	Sep. 24, 2011 Stock options	Sep. 29, 2012 Stock options Minimum	Sep. 29, 2012 Stock options Minimum	Sep. 29, 2012 Stock options Maximum	Sep. 29, 2012 Stock options Maximum	Sep. 29, 2012 Stock options Employees	Sep. 29, 2012 Stock options Board of Directors	Sep. 29, 2012 Stock option granted prior to May 2008	Sep. 29, 2012 Stock option granted prior to May 2008 Employees	Sep. 29, 2012 Stock option granted prior to May 2008 Board of Directors	Sep. 29, 2012 Restricted stock	Sep. 24, 2011 Restricted stock	Sep. 29, 2012 Restricted stock Minimum	Sep. 29, 2012 Restricted stock Maximum	Sep. 29, 2012 2005 Plan	Dec. 31, 2005 2005 Plan
Shareholders equity
Number of shares authorized																			2,710,518	410,518
Expiration term of awards (in years)				10 years								5 years
Vesting period (in years)							5 years		10 years	5 years	1 year		5 years	1 year			1 year	3 years
Number of Shares
Nonvested at the beginning of the period (in shares)															405,667
Granted (in shares)															177,437
Vested (in shares)															(63,667)
Nonvested at the end of the period (in shares)															519,437
Weighted-Average Grant Date Fair Value Per Share
Nonvested at the beginning of the period (in dollars per share)															$ 3.62
Granted (in dollars per share)															$ 6.49
Vested (in dollars per share)															$ 3.30
Nonvested at the end of the period (in dollars per share)															$ 4.64
Options Outstanding
Outstanding at the beginning of the period (in shares)				1,786,500
Granted (in shares)				197,500
Exercised (in shares)				(355,700)
Forfeited or expired (in shares)				(133,100)
Outstanding at the end of the period (in shares)		1,495,200		1,495,200
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)				$ 2.52
Granted (in dollars per share)				$ 6.55
Exercised (in dollars per share)				$ 2.50
Forfeited or expired (in dollars per share)				$ 2.83
Outstanding at the end of the period (in dollars per share)		$ 3.04		$ 3.04
Intrinsic value
Intrinsic value related to options outstanding		$ 4,127,333		$ 4,127,333
Closing stock price (in dollars per share)		$ 5.69		$ 5.69
Weighted Average Remaining Contractual Life
Weighted Average Remaining Contractual Life				5 years 9 months 4 days
Additional disclosures
Share-based compensation expenses				600,000	300,000										300,000	400,000
Unrecognized costs related to non-vested awards granted															1,000,000
Unrecognized costs related to non-vested stock option awards granted		1,300,000		1,300,000
Weighted average period for recognition of unrecognized compensation costs (in years)				2 years 9 months 18 days											1 year 1 month 6 days
Weighted-average assumptions used to estimate fair value of each stock option grant
Expected dividend yield (as a percent)		0.00%	0.00%	0.00%	0.00%
Expected volatility (as a percent)		56.00%	58.00%		58.00%		56.00%		58.00%
Risk-free interest rate (as a percent)		1.70%
Risk-free interest rate, minimum (as a percent)			3.20%	1.70%	3.20%
Risk-free interest rate, maximum (as a percent)			3.50%	3.50%	3.50%
Expected life			6 years 6 months		6 years 6 months	5 years 6 months	5 years 6 months	6 years 6 months	6 years 6 months
Issuer Purchases of Equity Securities
Authorized amount of stock re-purchase	$ 3,000,000