Common Stock, Dividends, Rate Increase, Percent.

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- Definition

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

+ References

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

The amount authorized by an entity's Board of Directors under a stock repurchase plan.

+ Details

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Balance Type:	credit
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- Definition

Reflects the known or estimated financial effect of the event, or transaction that occurred between the balance sheet date and the date the financial statements are issued or available to be issued.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Name Accounting Standards Codification
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 165
-Paragraph 13
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

Describes the event or transaction that occurred between the balance sheet date and the date the financial statements are issued or available to be issued.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 11
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 165
-Paragraph 13
-Subparagraph a
-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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Date of subsequent event occurrence or of indication that subsequent event occurred.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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Subsequent Events (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	1 Months Ended			6 Months Ended
	Apr. 30, 2011	Oct. 31, 2008	Feb. 29, 2008	Jun. 30, 2011
Subsequent Event [Line Items]
Common Stock, Dividends, Rate Increase, Percent	20.00%
Share Repurchase Plan, Authorized Repurchase Amount	$ 129	$ 100	$ 400	$ 629
Quarterly [Member] \| Previous [Member]
Subsequent Event [Line Items]
Common Stock, Dividends, Per Share, Declared	$ 0.05
Quarterly [Member] \| Subsequent [Member]
Subsequent Event [Line Items]
Common Stock, Dividends, Per Share, Declared	$ 0.06
Annual [Member] \| Previous [Member]
Subsequent Event [Line Items]
Common Stock, Dividends, Per Share, Declared	$ 0.2
Annual [Member] \| Subsequent [Member]
Subsequent Event [Line Items]
Common Stock, Dividends, Per Share, Declared	$ 0.24
Dividend Declared [Member]
Subsequent Event [Line Items]
Subsequent Event, Date				Jul. 07, 2011
Subsequent Event, Description				Common Stock cash dividend declared. The cash dividends are for the period from May 1, 2011 to July 31, 2011 and will be paid on August 1, 2011 to holders of record as of July 18, 2011.
Subsequent Event, Amount				$ 9
Common Stock, Dividends, Per Share, Declared				$ 0.06