Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 369,373	$ 312,069
Accounts receivable:
Billed receivables	540,584	437,797
Unbilled receivables	418,288	319,205
Allowance for doubtful accounts and unbilled services	(265,500)	(202,394)
Accounts receivable, net	693,372	554,608
Current portion of notes receivable	35,106	29,228
Prepaid expenses and other current assets	80,810	69,448
Total current assets	1,178,661	965,353
Property and equipment, net	93,672	84,577
Operating lease assets	159,777
Goodwill	1,202,767	1,172,316
Other intangible assets, net	38,432	34,633
Notes receivable, net	69,033	84,471
Other assets	40,800	37,771
Total assets	2,783,142	2,379,121
Current liabilities
Accounts payable, accrued expenses and other	158,936	104,600
Accrued compensation	416,903	333,536
Billings in excess of services provided	36,698	44,434
Total current liabilities	612,537	482,570
Long-term debt, net	275,609	265,571
Noncurrent operating lease liabilities	176,378
Deferred income taxes	151,352	155,088
Other liabilities	78,124	127,067
Total liabilities	1,294,000	1,030,296
Commitments and contingent liabilities (Note 15)
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 — 37,390 (2019) and 38,147 (2018)	374	381
Additional paid-in capital	216,162	299,534
Retained earnings	1,413,453	1,196,727
Accumulated other comprehensive loss	(140,847)	(147,817)
Total stockholders' equity	1,489,142	1,348,825
Total liabilities and stockholders' equity	$ 2,783,142	$ 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.

Name:	us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent
Namespace Prefix:	us-gaap_
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.