Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 16,975	$ 15,022	$ 14,638
Adjustments to reconcile net income to net cash provided from operating activities:
Depreciation and amortization	7,906	5,653	4,935
Provision for bad debts - accounts receivable	867	1,002	512
Share-based compensation expense	2,264	1,664	1,638
Deferred income tax (benefit) provision	(665)	5,114	(1,940)
Gain on foreign currency transactions			(264)
Gain on disposals of property, plant and equipment		(1,048)
Change in fair value of acquisition-related contingent liabilities	(1,116)	(89)	(31)
Changes in assets and liabilities, net of acquisition of businesses:
Accounts receivable - trade	(4,886)	(4,731)	(7,244)
Accounts receivable - other	105	1,237	177
Contract asset	(3,382)
Inventories	3,501	4,250	(5,427)
Prepaid expenses and other current assets	1,550	(4,151)	2,203
Other assets	(1,257)	(4,504)	(1,029)
Accounts payable and other current liabilties	(1,344)	3,362	2,030
Long-term pension liability	(128)	(2,577)	829
Other long-term liabilities	(526)	2,523	962
Net cash provided from operating activities	19,864	22,727	11,989
CASH FLOWS FROM INVESTING ACTIVITIES
Additions to property, plant and equipment	(4,869)	(4,248)	(7,385)
Proceeds from disposals of property, plant and equipment		2,858
Acquisition of businesses, net of acquired cash	(85,597)	(7,988)	(15,161)
Net cash used in investing activities	(90,466)	(9,378)	(22,546)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from long-term debt	206,025	74,387	125,067
Repayment of long-term debt	(127,439)	(77,573)	(106,827)
Payment of cash dividends	(5,836)	(5,269)	(4,707)
Payment of acquisition-related contingent liabilities	(2,861)	(1,800)	(1,800)
Proceeds received on exercise of stock options	727	1,872	1,504
Tax benefit from vesting of acquisition related restricted stock	445	650	990
Tax withholdings on exercise of stock rights	(17)	(1,186)	(405)
Common stock reacquired and retired	(2,906)		(714)
Net cash provided from (used in) financing activities	68,138	(8,919)	13,108
Effect of exchange rates on cash	(304)	51	62
Net (decrease) increase in cash and cash equivalents	(2,768)	4,481	2,613
Cash and cash equivalents balance, beginning of year	8,130	3,649	1,036
Cash and cash equivalents balance, end of year	$ 5,362	$ 8,130	$ 3,649