CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Operating activities:
Net income	$ 7,978	$ 11,915
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	3,293	3,190
Stock-based compensation expense	1,601	1,581
Deferred income taxes	(1,926)	475
(Loss) gain on disposal of assets	(187)	152
Changes in operating assets and liabilities, net of acquisitions:
Receivables	(7,111)	2,028
Prepaid expenses and other assets	3,881	(2,413)
Prepaid income taxes	2,458	0
Accounts payable and accrued expenses	24,859	18,524
Income taxes payable	0	164
Net amounts due to/from governmental entities	(1,011)	(985)
Net cash provided by operating activities	33,835	34,631
Investing activities:
Purchases of property, building and equipment	(2,551)	(2,523)
Cash paid for acquisitions, primarily goodwill and intangible assets	(2,770)	(449)
Advanced payments on acquisitions	0	(4,487)
Net cash used in investing activities	(5,321)	(7,459)
Financing activities:
Proceeds from line of credit	13,000	5,000
Payments on line of credit	(32,000)	(14,000)
Proceeds from employee stock purchase plan	332	256
Payments on debt	(64)	(65)
Noncontrolling interest distributions	(3,086)	(2,391)
Withholding taxes paid on stock-based compensation	(3,467)	(2,569)
Purchase of additional controlling interest	(55)
Sale of noncontrolling interest	3,322	114
Net cash (used in) financing activities	(22,018)	(13,655)
Change in cash	6,496	13,517
Cash at beginning of period	2,849	3,264
Cash at end of period	9,345	16,781
Supplemental disclosures of cash flow information:
Interest paid	1,397	721
Income taxes paid	$ 792	$ 4,580