Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&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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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.

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No definition available.

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Common Stock Dividends (Narrative) (Details) - $ / shares				3 Months Ended		6 Months Ended
	Jun. 05, 2017	Apr. 03, 2017	Feb. 21, 2017	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016
Dividends Payable [Line Items]
Common stock, quarterly dividends, per share, declared			$ 0.51
Annual dividend approved by Board of Directors			$ 2.04	$ 0.00	$ 0.00	$ 2.04	$ 2.00
Dividend paid
Dividends Payable [Line Items]
Dividends	Jun. 05, 2017	Apr. 03, 2017