Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 258,470	$ 312,069
Accounts receivable:
Billed receivables	552,253	437,797
Unbilled receivables	455,342	319,205
Allowance for doubtful accounts and unbilled services	(268,132)	(202,394)
Accounts receivable, net	739,463	554,608
Current portion of notes receivable	32,368	29,228
Prepaid expenses and other current assets	65,849	69,448
Total current assets	1,096,150	965,353
Property and equipment, net	92,135	84,577
Operating lease assets	152,064
Goodwill	1,197,406	1,172,316
Other intangible assets, net	41,247	34,633
Notes receivable, net	78,800	84,471
Other assets	32,467	37,771
Total assets	2,690,269	2,379,121
Current liabilities
Accounts payable, accrued expenses and other	158,136	104,600
Accrued compensation	354,299	333,536
Billings in excess of services provided	34,349	44,434
Total current liabilities	546,784	482,570
Long-term debt, net	273,055	265,571
Noncurrent operating lease liabilities	171,410
Deferred income taxes	159,406	155,088
Other liabilities	78,380	127,067
Total liabilities	1,229,035	1,030,296
Commitments and contingent liabilities
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 — 37,629 (2019) and 38,147 (2018)	376	381
Additional paid-in capital	240,508	299,534
Retained earnings	1,384,392	1,196,727
Accumulated other comprehensive loss	(164,042)	(147,817)
Total stockholders' equity	1,461,234	1,348,825
Total liabilities and stockholders' equity	$ 2,690,269	$ 2,379,121

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.