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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Consolidated Statements Of Changes In Shareholders' Equity (USD $) In Thousands	Total	Preference Shares	Common Shares	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Retained Earnings
Beginning of period at Dec. 31, 2013		$ 400,000	$ 43,646	$ 0	$ 4,131	$ 3,456,607
Issuance of shares			0	0
Repurchase of shares			(2,978)	4,179		(278,252)
Change in noncontrolling interests				(35)
Exercise of options and issuance of restricted stock awards			188	(4,144)
Change in net unrealized gains on investments	168				(168)
Net income	199,366us-gaap_ProfitLoss					199,366
Net income attributable to noncontrolling interests	(42,768)					(42,768)
Dividends on common shares						(11,899)
Dividends on preference shares	(5,595)us-gaap_DividendsPreferredStock					(5,595)
Total shareholders’ equity	3,762,278
End of period at Mar. 31, 2014		400,000	40,856	0	3,963	3,317,459
Beginning of period at Dec. 31, 2014	3,865,715us-gaap_StockholdersEquity	400,000	38,442	0	3,416	3,423,857
Issuance of shares			7,435	754,384
Repurchase of shares			0	0		0
Change in noncontrolling interests				(260)
Exercise of options and issuance of restricted stock awards			149	817
Change in net unrealized gains on investments	74				(74)
Net income	213,100us-gaap_ProfitLoss					213,100
Net income attributable to noncontrolling interests	(39,662)					(39,662)
Dividends on common shares						(13,720)
Dividends on preference shares	(5,595)us-gaap_DividendsPreferredStock					(5,595)
Total shareholders’ equity	4,782,289
End of period at Mar. 31, 2015	$ 4,782,289us-gaap_StockholdersEquity	$ 400,000	$ 46,026	$ 754,941	$ 3,342	$ 3,577,980