Accounts Receivable - Narratives (Details) $ in Millions	3 Months Ended
Apr. 28, 2018 USD ($)
Receivables [Abstract]
Increase in trade receivables	$ 2.1
Increase in unbilled receivables	$ 3.9

The increase (decrease) during the reporting period of the amount of revenue for work performed for which billing has not occurred, net of uncollectible accounts.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Name:	us-gaap_IncreaseDecreaseInUnbilledReceivables
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration