Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Activities
Net income	$ 43,209	$ 41,151	$ 36,094
Adjustments to reconcile net income to cash provided by operating activities:
Provision for doubtful accounts	965	469	31
Depreciation	18,988	10,645	8,898
Amortization of intangibles	3,113	2,005	0
Amortization of debt issuance	214	183	126
Stock-based compensation expense	1,057	1,986	1,501
Excess tax expense (benefit) from stock-based payment arrangements	142	(94)	0
Provision for deferred income tax expense (benefit)	2,804	(108)	(877)
Gain on sale of property, plant and equipment	(4,046)	(911)	(237)
Changes in operating assets and liabilities, net of effect of acquisitions:
Accounts receivable	(9,657)	(12,596)	(10,515)
Inventories	9,759	(10,993)	776
Rental equipment	(11,699)	(5,184)	0
Prepaid expenses and other	(3,521)	6,661	(925)
Trade accounts payable and accrued liabilities	(1,708)	1,202	4,420
Income taxes payable	3,700	(3,075)	(4,565)
Other assets and liabilities, net	(760)	(1,131)	(3,100)
Net cash provided by operating activities	52,560	30,210	31,627
Investing Activities
Acquisitions, net of cash acquired	(3,465)	(196,467)	(1,002)
Purchase of property, plant and equipment	(15,479)	(9,806)	(13,639)
Proceeds from sale of property, plant and equipment	4,246	1,442	475
Net cash used in investing activities	(14,698)	(204,831)	(14,166)
Financing Activities
Borrowings on bank revolving credit facility	79,000	273,000	0
Repayment on bank revolving credit facility	(125,000)	(83,000)	0
Principal payments on long-term debt and capital leases	(449)	(682)	(399)
Proceeds from issuance of long-term debt	0	767	0
Debt issuance cost	0	(818)	0
Dividends paid	(3,628)	(3,328)	(3,371)
Proceeds from exercise of stock options	2,023	903	1,286
Treasury stock repurchased	0	(34,204)	0
Excess tax (benefit) expense from stock-based payment arrangements	(142)	94	0
Net cash (used in) provided by financing activities	(48,196)	152,732	(2,484)
Effect of exchange rate changes on cash	(2,277)	(2,538)	692
Net change in cash and cash equivalents	(12,611)	(24,427)	15,669
Cash and cash equivalents at beginning of the year	39,533	63,960	48,291
Cash and cash equivalents at end of the year	26,922	39,533	63,960
Cash paid during the year for:
Interest	6,936	3,320	1,118
Income taxes	$ 18,709	$ 22,243	$ 21,580