Supplemental Financial Statement Data (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended
Nov. 30, 2014	Aug. 31, 2014	May 31, 2014	Feb. 28, 2014	Nov. 30, 2013	Aug. 31, 2013	May 31, 2013	Feb. 28, 2013	Nov. 30, 2014	Nov. 30, 2013	Nov. 30, 2012
Supplemental Financial Statement Data [Abstract]
Dividends paid per share (usd per share)	$ 0.37	$ 0.37	$ 0.37	$ 0.37	$ 0.34	$ 0.34	$ 0.34	$ 0.34	$ 1.48	$ 1.36	$ 1.24

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: 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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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration