Condensed Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
REVENUE	$ 633,224	$ 610,912
Cost of services	542,717	520,291
General and administrative expenses	48,086	51,723
OPERATING INCOME	42,421	38,898
Interest expense	(354)	(655)
Interest income	40	50
Other (expense), net	(121)	(22)
INCOME FROM OPERATIONS BEFORE INCOME TAXES AND EQUITY METHOD INVESTMENTS	41,986	38,271
Provision for income taxes	(9,657)	(9,591)
Equity in (losses) of unconsolidated subsidiaries	(1)	(1)
NET INCOME	$ 32,328	$ 28,679
Class A common stock
BASIC EARNINGS PER SHARE:
Basic earnings per share	$ 0.80	$ 0.71
DILUTED EARNINGS PER SHARE:
Diluted earnings per share	0.79	0.71
Class B common stock
BASIC EARNINGS PER SHARE:
Basic earnings per share	0.80	0.71
DILUTED EARNINGS PER SHARE:
Diluted earnings per share	$ 0.79	$ 0.71