Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 179,241	$ 312,069
Accounts receivable:
Billed receivables	504,003	437,797
Unbilled receivables	389,805	319,205
Allowance for doubtful accounts and unbilled services	(237,681)	(202,394)
Accounts receivable, net	656,127	554,608
Current portion of notes receivable	29,206	29,228
Prepaid expenses and other current assets	56,640	69,448
Total current assets	921,214	965,353
Property and equipment, net	84,522	84,577
Operating lease assets	146,389	0
Goodwill	1,174,742	1,172,316
Other intangible assets, net	32,876	34,633
Notes receivable, net	75,148	84,471
Other assets	30,010	37,771
Total assets	2,464,901	2,379,121
Current liabilities
Accounts payable, accrued expenses and other	128,642	104,600
Accrued compensation	212,423	333,536
Billings in excess of services provided	50,400	44,434
Total current liabilities	391,465	482,570
Long-term debt, net	268,037	265,571
Noncurrent operating lease liabilities	173,874	0
Deferred income taxes	163,303	155,088
Other liabilities	66,200	127,067
Total liabilities	1,062,879	1,030,296
Commitments and contingent liabilities (Note 10)
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 — 38,027 (2019) and 38,147 (2018)	380	381
Additional paid-in capital	284,864	299,534
Retained earnings	1,259,372	1,196,727
Accumulated other comprehensive loss	(142,594)	(147,817)
Total stockholders' equity	1,402,022	1,348,825
Total liabilities and stockholders' equity	$ 2,464,901	$ 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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Period Type:	instant

- Definition

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.