CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Mar. 30, 2014		Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 493,035	[1]	$ 490,267	[2]
Short-term investments, at cost which approximates market	15,690	[1]	15,769	[2]
Accounts receivable, net	217,299	[1]	204,449	[2]
Inventories	91,614	[1]	89,169	[2]
Prepaid expenses and other current assets	17,132	[1]	15,463	[2]
Total current assets	834,770	[1]	815,117	[2]
Property, plant and equipment, less accumulated depreciation and depletion - March 30, 2014 - $988,047; December 31, 2013 - $976,265	306,379	[1]	306,071	[2]
Goodwill	64,274	[1]	64,432	[2]
Other assets and deferred charges	31,821	[1]	31,927	[2]
Total assets	1,237,244	[1]	1,217,547	[2]
Current liabilities:
Short-term debt	4,753	[1]	5,504	[2]
Current maturities of long-term debt	8,200	[1]	8,200	[2]
Accounts payable	109,546	[1]	94,855	[2]
Other current liabilities	57,823	[1]	72,335	[2]
Total current liabilities	180,322	[1]	180,894	[2]
Long-term debt	75,000	[1]	75,000	[2]
Accrued Pension and Post-Retirement Benefits	58,056	[1]	57,893	[2]
Other non-current liabilities	29,180	[1]	29,352	[2]
Total liabilities	342,558	[1]	343,139	[2]
Shareholders' equity:
Common stock	4,769	[1]	4,756	[2]
Additional paid-in capital	364,656	[1]	361,460	[2]
Retained earnings	1,120,145	[1]	1,106,252	[2]
Accumulated other comprehensive loss	(28,224)	[1]	(31,265)	[2]
Less common stock held in treasury	(593,665)	[1]	(593,665)	[2]
Total MTI shareholders' equity	867,681	[1]	847,538	[2]
Non-controlling interest	27,005	[1]	26,870	[2]
Total shareholders' equity	894,686	[1]	874,408	[2]
Total liabilities and shareholders' equity	$ 1,237,244	[1]	$ 1,217,547	[2]

[1] Unaudited

[2] Condensed from audited financial statements