Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Operating activities
Net income	$ 196,758	$ 155,093
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	25,631	23,655
Amortization and impairment of intangible assets	8,515	7,440
Acquisition-related contingent consideration	(1,014)	4,652
Provision for expected credit losses	14,816	15,608
Share-based compensation	17,150	17,576
Amortization of debt discount and issuance costs and other	8,551	9,073
Deferred income taxes	5,128	(1,658)
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable, billed and unbilled	(115,544)	(86,491)
Notes receivable	4,392	3,346
Prepaid expenses and other assets	1,145	8,294
Accounts payable, accrued expenses and other	(22,745)	7,713
Income taxes	18,025	(14,635)
Accrued compensation	2,803	(18,985)
Billings in excess of services provided	(7,691)	10,296
Net cash provided by operating activities	155,920	140,977
Investing activities
Payments for acquisition of businesses, net of cash received	(9,833)	(25,271)
Purchases of property and equipment and other	(52,441)	(25,105)
Net cash used in investing activities	(62,274)	(50,376)
Financing activities
Borrowings under revolving line of credit	377,500	149,500
Repayments under revolving line of credit	(352,500)	(124,500)
Purchase and retirement of common stock	(46,133)	(175,832)
Share-based compensation tax withholdings and other	(8,277)	(5,195)
Payments for business acquisition liabilities	(7,496)	(3,948)
Deposits	1,928	4,561
Net cash used in financing activities	(34,978)	(155,414)
Effect of exchange rate changes on cash and cash equivalents	(11,094)	98
Net increase (decrease) in cash and cash equivalents	47,574	(64,715)
Cash and cash equivalents, beginning of period	294,953	369,373
Cash and cash equivalents, end of period	342,527	304,658
Supplemental cash flow disclosures
Cash paid for interest	8,756	7,115
Cash paid for income taxes, net of refunds	31,240	61,636
Non-cash investing and financing activities:
Issuance of stock units under incentive compensation plans	2,603	2,314
Purchase and retirement of common stock not yet paid	0	8,540
Business acquisition liabilities not yet paid	0	3,460
Non-cash additions to property and equipment	$ 4,435	$ 1,203

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.