Revisions in Estimates (Tables)

12 Months Ended

Dec. 31, 2015

Construction [Member]

Change in Accounting Estimate [Line Items]

Schedule of Change in Accounting Estimate

Decreases

Years Ended December 31,		2015		2014		2013
Number of projects with downward estimate changes		5		6		5
Range of reduction in gross profit from each project, net	$	1.0 - 3.3	$	1.6 - 4.1	$	1.2 - 7.4
Decrease on project profitability	$	10.8	$	16.5	$	17.8

Increases

Years Ended December 31,		2015		2014		2013
Number of projects with upward estimate changes		14		7		6
Range of increase in gross profit from each project, net	$	1.1 - 6.6	$	1.0 - 1.8	$	1.1 - 3.7
Increase on project profitability	$	30.7	$	9.2	$	16.1

Large Project Construction [Member]

Change in Accounting Estimate [Line Items]

Schedule of Change in Accounting Estimate

Decreases

Years Ended December 31,		2015		2014		2013
Number of projects with downward estimate changes		6		3		5
Range of reduction in gross profit from each project, net	$	1.0 - 5.5	$	1.1 - 16.8	$	1.9 - 26.8
Decrease on project profitability	$	20.3	$	19.9	$	52.0

Increases

Years Ended December 31,		2015		2014		2013
Number of projects with upward estimate changes		7		12		7
Range of increase in gross profit from each project, net	$	1.5 - 6.7	$	1.0 - 15.2	$	2.6 - 41.3
Increase on project profitability	$	27.9	$	66.8	$	77.5