4. Employee Retirement Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 27, 2013	Sep. 28, 2012	Sep. 27, 2013	Sep. 28, 2012	Jul. 15, 2013	Sep. 27, 2013 Supplemental Executive Retirement Plan	Sep. 28, 2012 Supplemental Executive Retirement Plan	Sep. 27, 2013 Supplemental Executive Retirement Plan	Sep. 28, 2012 Supplemental Executive Retirement Plan	Sep. 27, 2013 Pension Plans, Defined Benefit	Sep. 28, 2012 Pension Plans, Defined Benefit	Sep. 27, 2013 Pension Plans, Defined Benefit	Sep. 28, 2012 Pension Plans, Defined Benefit	Sep. 27, 2013 Insurance premium due to the PBGC	Sep. 27, 2013 Federal excise tax related to non-payment of minimum pension funding	Oct. 15, 2013 Subsequent Event
Unfunded obligation of the Pension Plan	$ 28,025		$ 28,025
Defined Benefit Plans, Estimated Future Employer Contributions in Current Fiscal Year			2,077
Defined Benefit Contributions, unpaid contributions lien trigger amount			1,000
Unpaid pension plan trust contributions lien					1,410											2,129
Total unpaid contributions to satisfy regulatory funding standards including interest																2,129
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months						492		492
Pension	249	590	618	1,699										47	88
Net periodic benefit expense						46	54	138	161	115	536	345	1,538
Actuarial loss reclassified from accumulated other comprehensive loss	$ 182		$ 546