Costs and estimated earnings in excess of billings (Tables)

9 Months Ended

Sep. 30, 2014

Costs and estimated earnings in excess of billings [Abstract]

Costs and estimated earnings in excess of billings

	September 30,		December 31,
	2014		2013
	(in thousands)
Unbilled costs and profits incurred to date*	$	261,435	$	204,276
Unapproved change orders		137,985		146,787
Claims		320,757		222,185
	$	720,177	$	573,248

*  Represents the excess of contract costs and profits recognized to date on the percentage of completion accounting method over the amount of contract billings to date on certain contracts.