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

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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

+ Details

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- Definition

Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Dividends (Details Textual) - USD ($) $ / shares in Units, $ in Millions							1 Months Ended					3 Months Ended
	May 03, 2017	Apr. 14, 2017	Mar. 03, 2017	Jul. 08, 2016	Jun. 01, 2016	Mar. 02, 2016	Dec. 23, 2016	Nov. 21, 2016	Sep. 30, 2016	Aug. 30, 2016	Apr. 15, 2016	Mar. 31, 2017	Mar. 31, 2016
Common Stock, Dividends, Per Share, Declared												$ 0.30	$ 0.25
Dividends		$ 1.8		$ 1.5			$ 2.9		$ 1.8		$ 1.5
Subsequent Event [Member]
Dividends Payable, Date to be Paid	Jun. 09, 2017
Dividends Payable, Date of Record	May 22, 2017
Dividends	$ 1.8
Common Class [Member]
Common Stock, Dividends, Per Share, Declared			$ 0.30		$ 0.25	$ 0.25		$ 0.30		$ 0.30
Common Class [Member] \| Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared	$ 0.30
Common Class B [Member]
Common Stock, Dividends, Per Share, Declared			$ 0.30		$ 0.25	$ 0.25		$ 0.20		$ 0.30
Common Class B [Member] \| Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared	$ 0.30