Disposition of Assets (Narrative) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012
Income Statement [Abstract]
Proceeds from sale of subsidiary			$ 1,108	$ 0
Loss on sale of subsidiary			608	0
Gain on sale of building	11,749	0	11,749	0
Loss from discontinued operation, net of income taxes	(611)	(3,010)	(4,087)	(17,621)
From discontinued operation (in US dollars per share)	$ (0.01)	$ (0.04)	$ (0.06)	$ (0.26)
Restructuring reserve	174	396	174	396	194	53
United Kingdom Construction [Member]
Income Statement [Abstract]
Revenues	3,166	23,752	17,149	69,973
Loss from discontinued operation, net of income taxes	(611)	(3,010)	(4,087)	(17,621)
From discontinued operation (in US dollars per share)	$ (0.01)	$ (0.04)	$ (0.06)	$ (0.26)
Restructuring reserve	2,200		2,200
Assets of discontinued operation:
Current assets	10,927		10,927		26,630
Non-current assets	359		359		833
Liabilities of discontinued operation:
Current liabilities	15,555		15,555		41,024
Non-current liabilities	140		140		513
United States Building Services [Member]
Income Statement [Abstract]
Proceeds from sale of subsidiary			1,100
Loss on sale of subsidiary			$ 600