Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
ASSETS
Cash and cash equivalents	$ 6,924	$ 41,193
Receivables—net	428,755	400,621
Prepaid expenses	30,206	26,243
Taxes receivable—current	14,339	21,968
Other current assets	6,921	6,354
Total Current Assets	487,145	496,379
Goodwill	1,237,733	1,237,894
Other intangible assets—net	195,352	202,231
Property and equipment—net	128,242	121,296
Operating lease right of use assets	89,108	94,825
Employee supplemental savings plan assets	38,206	37,848
Investments	11,548	11,549
Other assets	13,065	11,642
TOTAL ASSETS	2,200,399	2,213,664
LIABILITIES
Accounts payable	122,549	142,360
Accrued salaries and related expenses	120,875	123,953
Contract liabilities	30,383	37,218
Operating lease obligations—current	30,374	30,105
Accrued expenses and other current liabilities	9,990	15,177
Total Current Liabilities	314,171	348,813
Deferred income taxes	143,100	141,638
Operating lease obligations—long term	76,463	80,242
Accrued retirement	32,560	36,310
Long-term debt	21,500	15,000
Other long-term liabilities	12,177	12,249
TOTAL LIABILITIES	599,971	634,252
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY
Additional paid-in capital	549,811	545,717
Treasury stock	(9,158)	(9,158)
Retained earnings	1,059,608	1,042,676
Accumulated other comprehensive loss	(242)	(230)
TOTAL STOCKHOLDERS' EQUITY	1,600,428	1,579,412
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	2,200,399	2,213,664
Class A common stock
STOCKHOLDERS' EQUITY
Common stock	277	275
TOTAL STOCKHOLDERS' EQUITY	277	275
Class B common stock
STOCKHOLDERS' EQUITY
Common stock	132	132
TOTAL STOCKHOLDERS' EQUITY	$ 132	$ 132