Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net income	$ 6,394	$ 6,364
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization of property and equipment	7,978	6,552
Amortization of intangibles	7,128	6,416
Amortization of deferred financing costs and debt discount	302	102
Provision for doubtful accounts	896	1,231
Gain on sale of property and equipment	(185)	(107)
Noncash stock compensation	2,240	480
Changes in assets and liabilities, excluding effects of acquisitions
Accounts receivable	(7,058)	(3,200)
Inventories	(2,420)	(894)
Other assets	(4,139)	(722)
Accounts payable	(57)	(1,781)
Income taxes payable/receivable	1,303	3,106
Other liabilities	(6,297)	(1,873)
Net cash provided by operating activities	6,085	15,674
Cash flows from investing activities
Purchases of investments	(17,782)
Maturities of short term investments	19,000
Purchases of property and equipment	(10,237)	(7,776)
Acquisitions of businesses, net of cash acquired of $0 and $247, respectively	(11,505)	(106,873)
Proceeds from sale of property and equipment	283	203
Other	(1,050)	(550)
Net cash used in investing activities	(21,291)	(114,996)
Cash flows from financing activities
Payments on term loan under credit agreement applicable to respective period (Note 6)	(750)	(1,250)
Proceeds from delayed draw term loan under credit agreement applicable to respective period (Note 6)		112,500
Proceeds from vehicle and equipment notes payable	4,510	4,331
Debt issuance costs	(1)	(833)
Principal payments on long-term debt	(3,092)	(2,117)
Principal payments on capital lease obligations	(1,629)	(1,882)
Acquisition-related obligations	(1,740)	(1,248)
Repurchase of common stock	(24,640)
Surrender of common stock awards by employees	(56)	(54)
Net cash (used in) provided by financing activities	(27,398)	109,447
Net change in cash and cash equivalents	(42,604)	10,125
Cash and cash equivalents at beginning of period	62,510	14,482
Cash and cash equivalents at end of period	19,906	24,607
Supplemental disclosures of cash flow information Net cash paid during the period for:
Interest	3,914	2,044
Income taxes, net of refunds	899	650
Supplemental disclosure of noncash investing and financing activities
Common stock issued for acquisition of business		10,859
Vehicles capitalized under capital leases and related lease obligations	312	816
Seller obligations in connection with acquisition of businesses	3,093	2,302
Unpaid purchases of property and equipment included in accounts payable	$ 1,485	$ 609