Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The net amount of operating interest income (expense).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4K
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
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-Publisher FASB
-Name Accounting Standards Codification
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Changes in accumulated Other Comprehensive Income by Component Reclassification (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 25, 2018	Mar. 26, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest Income (Expense), Net	$ (19,536)	$ (18,882)	$ (84,748)	$ (83,686)	$ (86,785)
Provision (benefit) for taxes	19,199	27,719	(1,112)	(71,418)	$ (22,192)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Provision (benefit) for taxes	(347)	(371)
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Provision (benefit) for taxes	(347)	(371)	(1,484)	(1,361)
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member] \| Interest Rate Swap [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest Income (Expense), Net	2,365	2,365	9,459	8,671
Gains and Losses on Cash Flow Hedges [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 2,018	$ 1,994	$ 7,975	$ 7,310