Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) (USD $) In Thousands, except Per Share data	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Retained Earnings [Member]
Dividends paid on common stock (per share)	$ 0.31	$ 0.45
Accumulated Other Comprehensive Income (Loss) [Member]
Tax expense related to unrealized gains on securities available for sale	$ 26,185	$ 84,161
Tax expense related to reclassification adjustment for gains	40,526	37,750
Tax expense related to pension and other postretirement benefits adjustment	$ 1,192	$ 539

Tax expense to reclassification adjustment for gains.

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- Definition

Aggregate dividends paid 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

+ Details

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- Definition

Tax effects of the net changes to accumulated comprehensive income during the period related to benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 25

+ Details

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- Definition

Tax effect on gross appreciation or the gross loss in value of the total of unsold securities during the period being reported on.

+ References

+ Details

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