Goodwill and Other Intangible Assets (Rollforward of Other Intangible Assets) (Details) - USD ($) $ in Thousands			12 Months Ended
		Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2014
Other Intangible Assets [Line Items]
Other intangible assets, gross carrying amount						$ 354,200
Accumulated amortization						(103,800)
Other Intangible Assets [Roll Forward]
Other intangible assets, net, beginning balance			$ 199,379	$ 250,400
Amortization expense			(21,300)	(28,400)	$ (25,100)
Currency translation adjustments			1,600	(12,500)
Intangible asset impairment	[1]			(10,100)
Other activity, intangible assets			0
Other intangible assets, net, amortizing, ending balance		$ 70,600	70,600
Other intangible assets, net, ending balance		$ 179,711	179,711	199,379	250,400
Weighted Average [Member]
Other Intangible Assets [Roll Forward]
Remaining weighted average amortization period (in years)		9 years
Customer Relationships and Backlog [Member]
Other Intangible Assets [Line Items]
Other intangible assets, amortizing, gross carrying amount						199,800
Accumulated amortization						(90,300)
Other Intangible Assets [Roll Forward]
Other intangible assets, net, amortizing, beginning balance			80,800	109,500
Amortization expense			(17,900)	(26,500)
Currency translation adjustments, amortizing intangible assets			300	(2,200)
Intangible assets impairment, amortizing intangible assets	[1]			0
Other activity, intangible assets			0
Other intangible assets, net, amortizing, ending balance		$ 63,200	63,200	80,800	109,500
Customer Relationships and Backlog [Member] | Weighted Average [Member]
Other Intangible Assets [Roll Forward]
Remaining weighted average amortization period (in years)		9 years
Other Amortizing Intangible Assets [Member]
Other Intangible Assets [Line Items]
Other intangible assets, amortizing, gross carrying amount	[2]					26,300
Accumulated amortization	[2]					(13,500)
Other Intangible Assets [Roll Forward]
Other intangible assets, net, amortizing, beginning balance	[2]		10,400	12,800
Amortization expense	[2]		(3,400)	(1,900)
Currency translation adjustments, amortizing intangible assets	[2]		100	(500)
Intangible assets impairment, amortizing intangible assets	[1],[2]			0
Other activity, intangible assets	[2]		300
Other intangible assets, net, amortizing, ending balance	[2]	$ 7,400	7,400	10,400	12,800
Other Amortizing Intangible Assets [Member] | Weighted Average [Member]
Other Intangible Assets [Roll Forward]
Remaining weighted average amortization period (in years)	[2]	9 years
Trade Names [Member]
Other Intangible Assets [Line Items]
Other intangible assets, non-amortizing, carrying amount		$ 34,500	34,800	34,800	34,800	34,800
Other Intangible Assets [Roll Forward]
Other intangible assets, non-amortizing, beginning balance			34,800	34,800
Currency translation adjustments, non-amortizing intangible assets			0	0
Intangible asset impairment, non-amortizing intangible assets	[1]			0
Other activity, intangible assets			(300)
Other intangible assets, non-amortizing, ending balance		34,500	34,500	34,800	34,800
Pre-Qualifications [Member]
Other Intangible Assets [Line Items]
Other intangible assets, non-amortizing, carrying amount		74,600	73,400	93,300	93,300	$ 93,300
Other Intangible Assets [Roll Forward]
Other intangible assets, non-amortizing, beginning balance			73,400	93,300
Currency translation adjustments, non-amortizing intangible assets			1,200	(9,800)
Intangible asset impairment, non-amortizing intangible assets	[1]			(10,100)
Other activity, intangible assets			0
Other intangible assets, non-amortizing, ending balance		$ 74,600	$ 74,600	$ 73,400	$ 93,300

[1] Represents a non-cash impairment charge related to intangible assets associated with a reporting unit in western Canada.

[2] Consists principally of trade names and non-compete agreements.