CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 454,092	$ 395,152
Short-term investments, at cost which approximates market	14,178	18,494
Accounts receivable, less allowance for doubtful accounts: 2012 - $3,837; 2011 - $3,008	193,328	194,317
Inventories	84,569	90,760
Prepaid expenses and other current assets	18,318	21,566
Total current assets	764,485	720,289
Property, plant and equipment, less accumulated depreciation and depletion	317,669	318,134
Goodwill	65,829	64,671
Other assets and deferred charges	63,206	61,861
Total assets	1,211,189	1,164,955
Current liabilities:
Short-term debt	7,111	5,846
Current maturities of long-term debt	76,977	8,552
Accounts payable	98,371	103,354
Income taxes payable	8,862	5,334
Accrued compensation and related items	33,603	33,026
Restructuring liabilities	318	1,411
Other current liabilities	24,856	23,379
Total current liabilities	250,098	180,902
Long-term debt	8,478	85,449
Accrued pension and postretirement benefits	108,035	97,318
Other non-current liabilities	30,859	33,266
Total liabilities	397,470	396,935
Shareholders' equity:
Preferred stock, without par value; 1,000,000 shares authorized; none issued	0	0
Common stock at par, $010 par value; 100,000,000 shares authorized; issued 47,002,939 shares in 2012 and 46,751,260 shares in 2011	4,700	4,675
Additional paid-in capital	345,929	333,372
Retained earnings	1,032,869	963,130
Accumulated other comprehensive income (loss)	(51,198)	(45,331)
Less common stock held in treasury, at cost; 12,053,319 shares in 2012 and 11,479,279 shares in 2011	(541,889)	(514,234)
Total MTI shareholders' equity	790,411	741,612
Non-controlling interest	23,308	26,408
Total shareholders' equity	813,719	768,020
Total liabilities and shareholders' equity	$ 1,211,189	$ 1,164,955