Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 97,509	$ 82,985
Accounts receivable, net of allowances of $8,024 and $3,332 at March 31, 2020 and December 31, 2019, respectively	376,528	352,685
Accounts receivable, subcontractor	75,938	72,714
Prepaid expenses	19,950	11,669
Other current assets	30,669	40,446
Total current assets	600,594	560,499
Restricted cash, cash equivalents and investments	60,873	62,170
Fixed assets, net of accumulated depreciation of $138,589 and $132,900 at March 31, 2020 and December 31, 2019, respectively	116,718	104,832
Operating lease right-of-use assets	87,217	89,866
Other assets	104,829	120,254
Goodwill	851,459	595,551
Intangible assets, net of accumulated amortization of $164,848 and $151,417 at March 31, 2020 and December 31, 2019, respectively	638,443	398,474
Total assets	2,460,133	1,931,646
Current liabilities:
Accounts payable and accrued expenses	175,188	156,140
Accrued compensation and benefits	153,018	170,932
Current portion of notes payable	6,250	0
Current portion of operating lease liabilities	14,634	13,943
Deferred revenue	12,587	11,788
Other current liabilities	11,383	25,302
Total current liabilities	373,060	378,105
Revolving credit facility	225,000	0
Notes payable, less unamortized fees	858,906	617,159
Deferred income taxes, net	104,262	46,618
Operating lease liabilities	88,090	91,209
Other long-term liabilities	61,735	61,813
Total liabilities	1,711,053	1,194,904
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.01 par value; 10,000 shares authorized; none issued and outstanding at March 31, 2020 and December 31, 2019	0	0
Common stock, $0.01 par value; 200,000 shares authorized; 49,423 issued and 46,862 outstanding at March 31, 2020 and 49,283 issued and 46,722 outstanding at December 31, 2019	494	493
Additional paid-in capital	455,766	455,193
Treasury stock, at cost (2,561 shares at March 31, 2020 and December 31, 2019)	(119,143)	(119,143)
Retained earnings	411,858	400,047
Accumulated other comprehensive income	105	152
Total stockholders’ equity	749,080	736,742
Total liabilities and stockholders’ equity	$ 2,460,133	$ 1,931,646