Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Apr. 29, 2017	Apr. 30, 2016
Statement of Comprehensive Income [Abstract]
Net earnings	$ 321,018	$ 290,634
Other comprehensive (loss) income:
Change in unrealized loss on investments, net of tax	(16)	(12)
Comprehensive income	$ 321,002	$ 290,622

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e557-108580

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 942
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-Subparagraph (SX 210.9-04(22))
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-Name Accounting Standards Codification
-Topic 225
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-Paragraph 2
-Subparagraph (SX 210.5-03(20))
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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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