Shareholders' Equity Cash Dividends Declared Per Common Share (Details) - $ / shares		3 Months Ended
Oct. 27, 2016	Mar. 31, 2017	Mar. 31, 2016
Subsequent Event [Line Items]
Dividends declared (in dollars per share)	$ 0.58
Cash dividends declared and paid per common share (in dollars per share)		$ 0.58	$ 0.55

Aggregate dividends paid 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

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

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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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