CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
CURRENT ASSETS:
Cash and cash equivalents	$ 67,721	$ 54,896
Billed accounts receivable, less allowance for credit losses of $7,618 and $9,087, respectively	700,629	619,544
Unbilled accounts receivable, less allowance for credit losses of $815 and $784, respectively	59,473	45,596
Other receivables, less allowance for credit losses of $503 and $759, respectively	30,489	44,212
Inventories	19,908	13,472
Prepaid expenses and other	11,519	15,510
Costs and estimated earnings in excess of billings, less allowance for credit losses of $34 and $79, respectively	14,972	18,622
Total current assets	904,711	811,852
PROPERTY AND EQUIPMENT, NET	115,538	117,206
LEASE RIGHT-OF-USE ASSET	104,336	94,727
GOODWILL	526,964	464,392
IDENTIFIABLE INTANGIBLE ASSETS, NET	268,099	231,807
DEFERRED TAX ASSETS	22,812	29,401
OTHER NONCURRENT ASSETS	8,874	7,970
Total assets	1,951,334	1,757,355
CURRENT LIABILITIES:
Current maturities of long-term debt	5,958
Accounts payable	236,387	204,145
Accrued compensation and benefits	137,910	121,864
Billings in excess of costs and estimated earnings	244,578	226,237
Accrued self-insurance	19,930	49,166
Other current liabilities	97,499	91,492
Total current liabilities	742,262	692,904
LONG-TERM DEBT, NET	266,772	235,733
LEASE LIABILITIES	88,923	80,576
DEFERRED TAX LIABILITIES	1,339	1,339
OTHER LONG-TERM LIABILITIES	80,249	50,374
Total liabilities	1,179,545	1,060,926
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY:
Preferred stock, $.01 par, 5,000,000 shares authorized, none issued and outstanding
Common stock, $.01 par, 102,969,912 shares authorized, 41,123,365 and 41,123,365 shares issued, respectively	411	411
Treasury stock, at cost, 5,080,907 and 4,935,186 shares, respectively	(150,987)	(129,243)
Additional paid-in capital	326,493	322,451
Retained earnings	595,872	502,810
Total stockholders' equity	771,789	696,429
Total liabilities and stockholders' equity	$ 1,951,334	$ 1,757,355