Consolidated Balance Sheet (Parenthetical) (USD $)	Mar. 31, 2013	Dec. 31, 2012
Consolidated Balance Sheet [Abstract]
Accounts receivable, allowances	$ 11,933	$ 10,892
Properties and equipment, at cost, accumulated depreciation	169,719	164,607
Identifiable intangible assets, accumulated amortization	$ 30,791	$ 30,414
Capital stock - authorized	80,000,000	80,000,000
Capital stock - par value	$ 1	$ 1
Capital stock - issued	31,956,848	31,589,366
Treasury stock	13,185,316	13,057,270