Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 6,479	$ 5,917
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	4,109	3,507
Gain on sale of fixed assets	(4)	(31)
Share-based compensation	871	873
Excess tax benefit on share-based compensation	(126)	(219)
Deferred income taxes	224	283
Changes in operating assets and liabilities:
Receivables, net	(4,826)	(2,785)
Inventories	(366)	(642)
Prepaid expenses	(1,231)	(682)
Refundable income taxes	831	2,503
Other assets	(93)	105
Accounts payable	508	(666)
Accrued expenses	(2)	1,220
Other liabilities	205	(136)
Net cash provided by operating activities	6,579	9,247
Cash flows from investing activities:
Additions to property, plant, and equipment	(6,077)	(13,003)
Proceeds from sale of fixed assets	4	31
Net cash used in investing activities	(6,073)	(12,972)
Cash flows from financing activities:
Principal repayments of long-term debt	(758)	(745)
Proceeds from exercise of stock options, net of attestation	529	220
Excess tax benefit on share-based compensation	126	219
Repurchases of common stock		(587)
Payment of statutory withholdings for stock options exercised and restricted stock units vested	(89)	(79)
Net cash used in financing activities	(192)	(972)
Net increase (decrease) in cash and cash equivalents	314	(4,697)
Cash and cash equivalents at beginning of period	29,804	34,052
Cash and cash equivalents at end of period	$ 30,118	$ 29,355