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

+ References

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ 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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 405

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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Shareholders' Equity (Details) (USD $)	3 Months Ended		0 Months Ended
Shareholders' Equity (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 13, 2015
Class of Stock [Line Items]
Dividends declared per common share, in usd per share	$ 0.3	$ 0.29
Dividends declared and paid, Preference shares	$ 5,595,000us-gaap_DividendsPreferredStock	$ 5,595,000us-gaap_DividendsPreferredStock
Retained Earnings
Class of Stock [Line Items]
Dividends declared and paid, Preference shares	5,595,000	5,595,000
Dividends declared and paid, Common shares	13,720,000	11,899,000
Common Shares
Class of Stock [Line Items]
Dividends declared per common share, in usd per share				$ 0.30
Dividends per common share, in usd per share			$ 0.3
Share repurchase program, Remaining authorized aggregate amount	$ 500,000,000		$ 500,000,000