Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Net income	$ 127,149	$ 130,023	$ 142,742
Other comprehensive income, net of tax:
Net unrealized holding gains (losses) on securities available for sale arising during period (tax effects of $35,960, $(11,300), and $29,863)	66,782	(20,985)	55,460
Reclassification adjustment for gains on securities available for sale included in net income (tax effects of $(6,050), $(11,623), and $(4,185))	(11,235)	(21,586)	(7,771)
Reclassification adjustment for impairment charges on available for sale securities included in net income (tax effects of $342, $2,946, and $0)	635	5,470
Comprehensive income	$ 183,331	$ 92,922	$ 190,431

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Reclassification adjustment for unrealized gains or losses realized upon the sale of securities, after tax.

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