Segment Information Segment Reporting (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) Segment	Mar. 31, 2018 USD ($)
Segment Reporting [Abstract]
Number of Reportable Segments \| Segment	2
Segment Reporting Information [Line Items]
Total revenue	$ 91,343	$ 84,459
Gross Profit	48,923	46,218
Operating Income (Loss)	5,544	1,837
Interest Expense	197	240
Other Nonoperating Income (Expense)	472	287
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	5,819	1,884
Lawson [Member]
Segment Reporting Information [Line Items]
Revenue	82,467	76,426
Gross Profit	45,619	42,922
Operating Income (Loss)	5,263	1,357
Bolt [Member]
Segment Reporting Information [Line Items]
Revenue	8,876	8,033
Gross Profit	3,304	3,296
Operating Income (Loss)	281	480
Product [Member]
Segment Reporting Information [Line Items]
Revenue	81,915	74,970
Product [Member] \| Lawson [Member]
Segment Reporting Information [Line Items]
Revenue	73,039	66,937
Gross Profit	40,604	36,842
Service [Member]
Segment Reporting Information [Line Items]
Revenue	9,428	9,489
Service [Member] \| Lawson [Member]
Segment Reporting Information [Line Items]
Revenue	9,428
Gross Profit	$ 5,015	$ 6,080

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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