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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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Disposition Of Assets (Components Of The Results Of Discontinued Operations For The UK Construction Operations) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Loss from discontinued operation, net of income taxes									$ (2,345)	$ (857)	$ (3,142)
Diluted loss per share from discontinued operation (in US dollars per share)	$ (0.02)	$ (0.01)	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ (0.01)	$ (0.04)	$ (0.01)	$ (0.05)
United Kingdom Construction
Income Statement [Abstract]
Revenues									$ 0	$ 863	$ 345
Loss from discontinued operation, net of income taxes									$ (2,345)	$ (857)	$ (3,142)
Diluted loss per share from discontinued operation (in US dollars per share)									$ (0.04)	$ (0.01)	$ (0.05)
Assets of discontinued operation:
Current assets	$ 0				$ 242				$ 0	$ 242
Liabilities of discontinued operation:
Current liabilities	$ 3,724				$ 2,811				$ 3,724	$ 2,811