Balance Sheet Parenthetical (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Allowance for doubtful accounts receivable	$ 22,923	$ 22,079
Accumulated depreciation of property and equipment	243,617	231,327
Accumulated amortization of intangible assets	110,131	132,927
Accumulated amortization of other assets	$ 28,611	$ 25,363
Preferred Stock, par value per share	$ 0.02	$ 0.02
Preferred Stock, shares authorized	10,000,000	10,000,000
Preferred Stock, shares issued	0	0
Common Stock, par value per share	$ 0.02	$ 0.02
Common Stock, shares authorized	90,000,000	90,000,000
Common Stock, shares issued	56,265,576	54,276,761
Treasury Stock, shares	3,669,074	3,650,519