CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 12,575	$ 6,539
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	18,256	17,593
Losses on sales and/or abandonment of property and equipment	53	289
Write-off of patents and intangible assets	14	119
Amortization of deferred credits	(85)	(88)
Amortization of long-term debt issuance costs	494	494
Deferred income taxes	383	19
Excess tax benefits from stock-based compensation	(1,420)	(236)
Stock-based compensation expense	1,085	663
Changes in operating assets and liabilities, net of effects from acquisitions:
Trade receivables	(2,793)	(7,152)
Employee receivables	20	44
Other receivables	942	(753)
Inventories	166	(4,094)
Prepaid expenses	(631)	(366)
Prepaid income taxes	(43)	3
Income tax refund receivables	(78)	24
Other assets	(2,887)	(641)
Trade payables	5,222	2,299
Accrued expenses	4,475	3,539
Advances from employees	262	371
Income taxes payable	2,909	759
Liabilities related to unrecognized tax benefits	0	(264)
Deferred compensation payable	822	532
Other long-term obligations	641	446
Total adjustments	27,807	13,600
Net cash provided by operating activities	40,382	20,139
Capital expenditures for:
Property and equipment	(25,366)	(18,716)
Intangible assets	(875)	(925)
Proceeds from sale-leaseback transactions	2,017	0
Proceeds from the sale of property and equipment	6	21
Cash paid in acquisitions, net of cash acquired	(2,250)	(1,450)
Net cash used in investing activities	(26,468)	(21,070)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock	5,144	3,528
Proceeds from issuance of long-term debt	65,339	71,734
Payments on long-term debt	(80,056)	(72,213)
Excess tax benefits from stock-based compensation	1,421	236
Contingent payments related to acquisitions	(180)	(38)
Payment of taxes related to an exchange of common stock	(660)	(220)
Net cash provided by (used in) financing activities	(8,992)	3,027
EFFECT OF EXCHANGE RATES ON CASH	(175)	(154)
NET INCREASE IN CASH AND CASH EQUIVALENTS	4,747	1,942
CASH AND CASH EQUIVALENTS:
Beginning of period	7,355	7,459
End of period	12,102	9,401
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Interest (net of capitalized interest of $185 and $213, respectively)	3,279	4,969
Income taxes	2,209	1,911
SUPPLEMENTAL DISCLOSURES OF NON-CASH INVESTING AND FINANCING ACTIVITIES
Property and equipment purchases in accounts payable	2,352	3,433
Merit common stock surrendered (166 and 108 shares, respectively) in exchange for exercise of stock options	3,317	1,641
Acquisition purchases in accrued expenses	$ 1,500	$ 0