Basis Of Presentation (Details) (USD $)	6 Months Ended	12 Months Ended	3 Months Ended	6 Months Ended
Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Dividend Declared [Member]	Jun. 30, 2013 Dividend Declared [Member]	Jun. 30, 2013 Dividend Declared [Member]
Subsequent Event [Line Items]
Subsequent Event, Date Evaluated, Description	The Company evaluated events and transactions that occurred after the balance sheet date but before financial statements were issued
Dividends payable, date declared					Jul. 19, 2013
Quarterly dividends per share	$ 0.88	$ 1.68	$ 0.49	$ 0.44

Aggregate dividends declared 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=6959260&loc=d3e187085-122770

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- Definition

Date the dividend to be paid was declared, 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

A description detailing whether the date through which subsequent events have been evaluated is the date the financial statements were issued or the date financial statements were available to be issued.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 855

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314015-165662

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