Subsequent Event (Details) - $ / shares	6 Months Ended
Jul. 31, 2019	Aug. 15, 2019
Subsequent Event [Line Items]
Dividend payable, date declared	Aug. 15, 2019
Dividend payable, date to be paid	Oct. 10, 2019
Dividend payable, date of record	Sep. 20, 2019
Subsequent Event
Subsequent Event [Line Items]
Dividend payable (usd per share)		$ 0.58

Date the declared dividend will be paid, in CCYY-MM-DD format.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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