v2.4.0.8

Subsequent Events (Details) (USD $) | 3 Months Ended | 6 Months Ended | 0 Months Ended
--- | --- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 | Aug. 07, 2013 Subsequent Event [Member] Dividend Declared [Member]
Subsequent Event [Line Items] |  |  |  |  |
Dividends declared per common share (in dollars per share) | $ 0.09 | $ 0.08 | $ 0.18 | $ 0.16 | $ 0.09
Dividends declared per Preference share (in dollars per share) | $ 0.515625 |  |  |  | $ 0.515625

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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=27012166&loc=d3e187085-122770 + Details
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Period Type: | duration

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- Definition Aggregate dividends declared during the period for each share of preferred stock outstanding. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration