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

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

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Subsequent Events Subsequent Events (Details Textual) - $ / shares				12 Months Ended
	Feb. 28, 2017	Feb. 21, 2017	Feb. 01, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Subsequent Event [Line Items]
Dividends declared per share (usd per share)				$ 2	$ 2.00	$ 1.25
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends Payable, Date to be Paid	Feb. 28, 2017
Dividends Payable, Date of Record		Feb. 21, 2017
Dividend Declared [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends declared per share (usd per share)			$ 0.5