Percent aggregate change in contract estimates impact on operating results is less than this percentage.

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- Definition

Revenue recognition.

+ References

No definition available.

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- Definition

Losses recognized in the current period on contracts which are expected to generate losses, which are probable and can be reasonably estimated, in a future period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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- Definition

The amount of costs incurred on unapproved change orders when it is probable that the cost will be recovered through a change in the contract price.

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Summary of Significant Accounting Policies - Revenue Recognition (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenue Recognition [Line Items]
Cumulative adjustment to retained earnings (less than)	$ (2,191,059)	$ (1,876,081)
Change orders and/or claims	$ 144,000	$ 137,800
Maximum
Revenue Recognition [Line Items]
Percent aggregate change in contract estimates impact on operating results is less than this percentage	5.00%	5.00%	5.00%
Alaska Power Plant Construction Project
Revenue Recognition [Line Items]
Losses on contracts		$ 54,800	$ 44,900
Accounting Standards Update 2014-09 \| Pro Forma
Revenue Recognition [Line Items]
Cumulative adjustment to retained earnings (less than)	$ 10,000