Earnings Per Share (EPS) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jul. 01, 2012	Jul. 03, 2011	Jul. 01, 2012	Jul. 03, 2011
Basic EPS
Net income attributable to MTI	$ 19,715	$ 16,413	$ 37,747	$ 32,194
Weighted average shares outstanding	17,724,000	18,177,000	17,721,000	18,227,000
Basic earnings per share attributable to MTI	$ 1.11	$ 0.90	$ 2.13	$ 1.77
Diluted EPS
Net income attributable to MTI	$ 19,715	$ 16,413	$ 37,747	$ 32,194
Weighted average shares outstanding	17,724,000	18,177,000	17,721,000	18,227,000
Dilutive effect of stock options and stock units	0.1	0.1	0.1	0.2
Weighted average shares outstanding , adjusted	17,790,000	18,290,000	17,795,000	18,353,000
Diluted earnings per share attributable to MTI	$ 1.11	$ 0.90	$ 2.12	$ 1.75
Anti-dilutive options not included in the weighted average common shares outstanding calculation			305,131	123,363