Revenue Recognition (Tables)

6 Months Ended

Jun. 30, 2020

Revenue from Contract with Customer [Abstract]

Schedule of Disaggregated Revenues

Revenues by geographical area and customer type were as follows:

	Three Months Ended June 30, 2020								Three Months Ended June 30, 2019
	Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total		Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total
	(In thousands)
United States:
Government	$	370,060	$	—	$	28,486	$	398,546	$	343,048	$	—	$	28,823	$	371,871
Non-Government	38,084		6,989		3,731		48,804		14,612		8,973		788		24,373
	$	408,144	$	6,989	$	32,217	$	447,350	$	357,660	$	8,973	$	29,611	$	396,244
Canada:
Non-Government	$	—	$	57,380	$	1,111	$	58,491	$	—	$	66,160	$	218	$	66,378
Other:
Non-Government	$	2,108	$	3,614	$	—	$	5,722	$	692	$	11,506	$	—	$	12,198
Segment Revenues	$	410,252	$	67,983	$	33,328	511,563		$	358,352	$	86,639	$	29,829	474,820
Eliminations							(7,043)								(3,589)
Revenues							$	504,520							$	471,231

	Six Months Ended June 30, 2020								Six Months Ended June 30, 2019
	Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total		Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total
	(In thousands)
United States:
Government	$	771,126	$	—	$	53,082	$	824,208	$	640,351	$	—	$	53,274	$	693,625
Non-Government	58,925		16,597		14,940		90,462		19,950		18,135		5,141		43,226
	$	830,051	$	16,597	$	68,022	$	914,670	$	660,301	$	18,135	$	58,415	$	736,851
Canada:
Non-Government	$	—	$	131,907	$	2,071	$	133,978	$	—	$	134,771	$	508	$	135,279
Other:
Non-Government	$	3,976	$	7,396	$	—	$	11,372	$	2,852	$	18,132	$	—	$	20,984
Segment Revenues	$	834,027	$	155,900	$	70,093	1,060,020		$	663,153	$	171,038	$	58,923	893,114
Eliminations							(13,292)								(5,429)
Revenues							$	1,046,728							$	887,685

Revenues by timing of transfer of goods or services were as follows:

	Three Months Ended June 30, 2020								Three Months Ended June 30, 2019
	Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total		Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total
	(In thousands)
Over time	$	410,204	$	61,590	$	33,328	$	505,122	$	358,294	$	72,793	$	29,829	$	460,916
Point-in-time	48		6,393		—		6,441		58		13,846		—		13,904
Segment Revenues	$	410,252	$	67,983	$	33,328	511,563		$	358,352	$	86,639	$	29,829	474,820
Eliminations							(7,043)								(3,589)
Revenues							$	504,520							$	471,231

	Six Months Ended June 30, 2020								Six Months Ended June 30, 2019
	Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total		Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total
	(In thousands)
Over time	$	833,943	$	138,775	$	70,093	$	1,042,811	$	663,027	$	143,454	$	58,923	$	865,404
Point-in-time	84		17,125		—		17,209		126		27,584		—		27,710
Segment Revenues	$	834,027	$	155,900	$	70,093	1,060,020		$	663,153	$	171,038	$	58,923	893,114
Eliminations							(13,292)								(5,429)
Revenues							$	1,046,728							$	887,685

Revenues by contract type were as follows:

	Three Months Ended June 30, 2020								Three Months Ended June 30, 2019
	Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total		Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total
	(In thousands)
Fixed-Price Incentive Fee	$	317,180	$	394	$	—	$	317,574	$	299,155	$	1,308	$	—	$	300,463
Firm-Fixed-Price	64,193		61,866		6,911		132,970		36,697		77,205		3,904		117,806
Cost-Plus Fee	28,827		—		24,018		52,845		22,286		8		25,780		48,074
Time-and-Materials	52		5,723		2,399		8,174		214		8,118		145		8,477
Segment Revenues	$	410,252	$	67,983	$	33,328	511,563		$	358,352	$	86,639	$	29,829	474,820
Eliminations							(7,043)								(3,589)
Revenues							$	504,520							$	471,231

	Six Months Ended June 30, 2020								Six Months Ended June 30, 2019
	Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total		Nuclear Operations Group		Nuclear Power Group		Nuclear Services Group		Total
	(In thousands)
Fixed-Price Incentive Fee	$	601,554	$	886	$	—	$	602,440	$	544,642	$	1,581	$	—	$	546,223
Firm-Fixed-Price	177,530		132,702		18,548		328,780		76,040		139,203		10,072		225,315
Cost-Plus Fee	54,823		—		46,511		101,334		42,139		8		48,315		90,462
Time-and-Materials	120		22,312		5,034		27,466		332		30,246		536		31,114
Segment Revenues	$	834,027	$	155,900	$	70,093	1,060,020		$	663,153	$	171,038	$	58,923	893,114
Eliminations							(13,292)								(5,429)
Revenues							$	1,046,728							$	887,685

Schedule of Contract Assets and Liabilities

	June 30,		December 31,
	2020		2019
	(In thousands)
Included in Contracts in progress:
Unbilled receivables	$	382,191	$	365,861
Retainages	$	46,767	$	46,670
Included in Other Assets:
Retainages	$	1,391	$	1,412
Advance billings on contracts	$	64,815	$	75,425

Schedule of Remaining Performance Obligations

Of the remaining performance obligations on our contracts with customers at June 30, 2020, we expect to recognize revenues as follows:

	2020		2021		Thereafter		Total
	(In approximate millions)
Nuclear Operations Group	$	722	$	1,098	$	2,094	$	3,914
Nuclear Power Group	178		209		384		771
Nuclear Services Group	33		5		5		43
Total Remaining Performance Obligations	$	933	$	1,312	$	2,483	$	4,728