Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 189,961	$ 216,158
Accounts receivable:
Billed receivables	390,996	365,385
Unbilled receivables	312,569	288,331
Allowance for doubtful accounts and unbilled services	(180,687)	(178,819)
Accounts receivable, net	522,878	474,897
Current portion of notes receivable	25,691	31,864
Prepaid expenses and other current assets	55,649	60,252
Total current assets	794,179	783,171
Property and equipment, net of accumulated depreciation	75,075	61,856
Goodwill	1,204,803	1,180,001
Other intangible assets, net of amortization	44,150	52,120
Notes receivable, net of current portion	98,105	104,524
Other assets	40,929	43,696
Total assets	2,257,241	2,225,368
Current liabilities
Accounts payable, accrued expenses and other	94,873	87,320
Accrued compensation	268,513	261,500
Billings in excess of services provided	46,942	29,635
Total current liabilities	410,328	378,455
Long-term debt, net	396,284	365,528
Deferred income taxes	124,471	173,799
Other liabilities	134,187	100,228
Total liabilities	1,065,270	1,018,010
Commitments and contingent liabilities (Note 13)
Stockholders' equity
Preferred stock, $0.01 par value; shares authorized — 5,000; none outstanding	0	0
Common stock, $0.01 par value; shares authorized — 75,000; shares issued and outstanding — 37,729 (2017) and 42,037 (2016)	377	420
Additional paid-in capital	266,035	416,816
Retained earnings	1,045,774	941,001
Accumulated other comprehensive loss	(120,215)	(150,879)
Total stockholders' equity	1,191,971	1,207,358
Total liabilities and stockholders' equity	$ 2,257,241	$ 2,225,368