Consolidated Balance Sheets (Parenthetical) (USD $)	Jun. 30, 2012	Dec. 31, 2011
Allowance for doubtful accounts	$ 5,041,000	$ 4,506,000
Accumulated amortization of other intangible assets	$ 8,993,000	$ 7,909,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	69,817,000	69,473,000
Common stock in treasury, shares	2,624,000	2,684,000

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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