CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Stock compensation expense	$ 6,057	$ 9,607
Changes in fair value of contingent consideration		144
Net of income tax provision	$ (67)	$ 100

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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