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Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Per diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation.

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Amount classified as liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Disposition of Assets (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Loss from discontinued operation, net of income taxes	$ (207)	$ (406)	$ (729)	$ (1,584)
From discontinued operation (in US dollars per share)	$ 0.00	$ (0.01)	$ (0.01)	$ (0.03)
Restructuring reserve	$ 49	$ 474	$ 49	$ 474	$ 201	$ 81
UNITED KINGDOM \| Discontinued Operations [Member] \| United Kingdom Construction [Member]
Income Statement [Abstract]
Revenues	(81)	40	863	108
Loss from discontinued operation, net of income taxes	$ (207)	$ (406)	$ (729)	$ (1,584)
From discontinued operation (in US dollars per share)	$ 0.00	$ (0.01)	$ (0.01)	$ (0.03)
Assets of discontinued operation:
Current assets	$ 360		$ 360		1,233
Liabilities of discontinued operation:
Current liabilities	3,511		3,511		$ 4,036
Employee Severance [Member] \| UNITED KINGDOM \| Discontinued Operations [Member] \| United Kingdom Construction [Member]
Income Statement [Abstract]
Restructuring reserve	$ 100		$ 100