Common Stock Data (Details) (USD $)	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011
Maximum [Member]
Sales price of common stock	$ 65.52	$ 58.49	$ 57.07	$ 57.97	$ 63.02	$ 63.11	$ 59.45	$ 66.49
Minimum [Member]
Sales price of common stock	$ 54.05	$ 49.98	$ 48.56	$ 50.79	$ 41.29	$ 54.95	$ 46.36	$ 46.63

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section H

Name:	us-gaap_SaleOfStockPricePerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant