CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current assets:
Restricted cash	$ 753	$ 813
Accounts receivable, reserves	12,006	14,074
Finite-Lived Intangible Assets [Line Items]
Intangible assets, accumulated amortization	49,606
Shareholders' equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	94,063,881	93,137,737
Common stock, shares outstanding (in shares)	94,063,881	93,137,737
Common stock subscribed, shares (in shares)	25,066	158,395
Purchased and Developed Software [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, accumulated amortization	17,385	13,884
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, accumulated amortization	$ 32,221	$ 25,007