Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Operating activities
Net income	$ 187,665	$ 126,887
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	22,384	24,548
Amortization and impairment of other intangible assets	5,838	6,297
Acquisition-related contingent consideration	717	355
Provision for doubtful accounts	13,552	11,951
Share-based compensation	14,060	12,219
Amortization of debt discount and issuance costs	8,666	2,604
Gain on sale of business	0	(13,031)
Other	248	751
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable, billed and unbilled	(191,644)	(130,369)
Notes receivable	2,521	2,659
Prepaid expenses and other assets	(5,817)	(174)
Accounts payable, accrued expenses and other	(7,332)	16,150
Income taxes	30,777	28,922
Accrued compensation	5,156	7,207
Billings in excess of services provided	(9,925)	(10,704)
Net cash provided by operating activities	76,866	86,272
Investing activities
Proceeds from sale of business	0	50,283
Payments for acquisition of businesses, net of cash received	(18,791)	0
Purchases of property and equipment	(27,026)	(27,841)
Other	55	741
Net cash provided by (used in) investing activities	(45,762)	23,183
Financing activities
Borrowings under revolving line of credit, net	0
Repayments of lines of credit		(100,000)
Proceeds from issuance of convertible notes	0	316,250
Payments of debt issue costs	0	(8,048)
Deposits	535	2,327
Purchase and retirement of common stock	(77,949)	(29,220)
Net issuance of common stock under equity compensation plans	3,176	31,241
Payments for business acquisition liabilities	(2,282)	(3,029)
Net cash provided by (used in) financing activities	(76,520)	209,521
Effect of exchange rate changes on cash and cash equivalents	(8,183)	(3,070)
Net increase (decrease) in cash and cash equivalents	(53,599)	315,906
Cash and cash equivalents, beginning of period	312,069	189,961
Cash and cash equivalents, end of period	258,470	505,867
Supplemental cash flow disclosures
Cash paid for interest	7,264	13,428
Cash paid for income taxes, net of refunds	29,885	20,324
Non-cash investing and financing activities:
Issuance of stock units under incentive compensation plans	1,413	1,059
Business acquisition liabilities not yet paid	$ 14,004	$ 0

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets, combined with the amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of indefinite-lived intangible assets, other than goodwill, to fair value. As a noncash expense, this element is added back to net income when calculating cash provided by (used in) operations using the indirect method.

No definition available.