Share Based Payments - Summary of Stock Options Outstanding and Activity (Parenthetical) (Details) - USD ($) $ in Millions	12 Months Ended
Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Cash received from exercise of stock options	$ 0.4	$ 0.1	$ 0.1

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=SL79508275-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

Name:	us-gaap_ProceedsFromStockOptionsExercised
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration