CONSOLIDATED STATEMENTS OF INCOME (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED STATEMENTS OF INCOME
Compensation and related costs, share-based compensation	$ 48,748	$ 45,384	$ 39,128
Income (loss) from discontinued operations, tax expense	$ 1,058	$ 2,556	$ 2,592

Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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