CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Accounts receivable, related allowances (in dollars)	$ 11,571	$ 18,303
Intangible assets, accumulated amortization (in dollars)	$ 215,485	$ 181,227
Common stock voting, par value (in dollars per share)	$ 0.0025	$ 0.0025
Common stock voting, shares authorized (in shares)	900,000,000	900,000,000
Common stock voting, shares issued (in shares)	255,592,901	255,052,811
Common stock voting, shares outstanding (in shares)	219,522,655	218,873,720
Treasury stock, shares (in shares)	36,070,246	36,179,091