The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 2
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase (decrease) to assets, excluding financial assets and goodwill, lacking physical substance with a finite life for foreign currency translation adjustments.

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No definition available.

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Goodwill and Intangible Assets (Intangible Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 25, 2016	Jun. 26, 2015	Jun. 24, 2016	Jun. 26, 2015
Changes in intangibles
Balance at beginning of year	$ 59,011		$ 59,011
Amortization	(4,700)	$ (6,200)	(9,477)	$ (13,400)
Foreign currency translation			1,916
Balance at end of year			51,450
Environmental and Nuclear
Changes in intangibles
Balance at beginning of year	30,096		30,096
Amortization			(2,353)
Foreign currency translation			2,250
Balance at end of year			29,993
Transportation
Changes in intangibles
Balance at beginning of year	22,731		22,731
Amortization			(5,559)
Foreign currency translation			(254)
Balance at end of year			16,918
Water
Changes in intangibles
Balance at beginning of year	$ 6,184		6,184
Amortization			(1,565)
Foreign currency translation			(80)
Balance at end of year			$ 4,539