Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Line Items]
Income taxes (benefit)		$ 1,917	$ 4,560	$ 1,787
Pre-tax income		$ 5,923	$ 12,451	$ 15,600
Effective tax rate		32.40%	36.60%	11.50%
Percentage of income tax expense attributable to Canada		82.10%
State income tax (net of federal benefit)		0.90%	2.40%	0.20%
US Federal income tax statutory rate		21.00%	35.00%	34.00%
Liability for uncertain tax positions taken on a foreign tax return		$ 800
Cash and cash equivalents held by foreign subsidiaries		25,800
Penalties and interest related to unrecognized tax benefits		100	$ 100
Income tax net operating loss carryforwards		13,000
Total deferred tax assets		2,798
Unrecognized tax benefits that would impact effective tax rate		800
Tax Act [Member]
Income Taxes [Line Items]
Income taxes (benefit)		$ 400
Tax Act [Member]
Income Taxes [Line Items]
Income taxes (benefit)	$ 5,400		300
Effective tax rate		24.66%
Tax expense for GILTI, net		$ 100
State income tax (net of federal benefit)		3.66%
US Federal income tax statutory rate		21.00%
Liability for uncertain tax positions taken on a foreign tax return	$ 5,100	$ 400	$ 5,100
Tax Act [Member] | FDII [Member]
Income Taxes [Line Items]
Income taxes (benefit)		$ (100)
Percentage of income tax rate deduction		37.50%
Tax Act [Member] | Deferred Tax Assets And Liabilities [Member]
Income Taxes [Line Items]
Income taxes (benefit)		$ 100