Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities:
Net income	$ 15,247	$ 12,835
Adjustments to reconcile net income to net cash provided by operating activities, net of acquisitions:
Depreciation and amortization	7,365	6,676
Deferred income taxes	372	397
Stock-based compensation	4,186	2,961
Amortization of debt issuance costs under the credit facility	533	450
Provision for doubtful accounts	168	214
Loss of disposal of assets	(90)
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable	(22,291)	(5,418)
Prepaid expenses and other current assets	2,822	2,007
Accounts payable	1,856	1,844
Accrued expenses and other long-term liabilities	(2,084)	2,713
Net cash provided by operating activities	8,084	24,679
Cash flows from investing activities:
Acquisitions of businesses, net of cash acquired	(53,224)	(62,347)
Purchases of property and equipment	(3,077)	(3,384)
Net cash used in investing activities	(56,301)	(65,731)
Cash flows from financing activities:
Proceeds from issuance of common stock, net of offering costs	172,945	76,618
Borrowings on revolver — credit facility	23,458
Borrowings on term loan — credit facility	19,600	60,420
Payments on term loan — credit facility	(245)	(1,688)
Payments for debt issuance costs under the credit facility	(361)	(73)
Payments on financing lease obligations	(54)	(952)
Cash received from exercise of stock options	2,077	450
Net cash provided by financing activities	217,420	134,775
Net change in cash	169,203	93,723
Cash, at beginning of period	70,406	53,754
Cash, at end of period	239,609	147,477
Supplemental disclosures of cash flow information:
Cash paid for interest	1,594	3,202
Cash paid for income taxes	5,808	4,234
Supplemental disclosures of non-cash investing and financing activities:
Contingent and deferred consideration accrued for acquisition		$ 847
Leasehold improvements acquired through tenant allowances	$ 682