Comprehensive Income (Components of Accumulated Other Comprehensive Income) (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Comprehensive Income [Abstract]
Beginning balance, OTTI Related Net Unrealized (Loss) Gain			$ (4,593)
Beginning balance, HTM related Net Unrealized Gain			11,144
Beginning balance, All Other Net Unrealized Gain			47,316
Beginning balance, Defined Benefit Pension and Post-retirement Plans			(46,843)
Beginning balance, Total Accumulated OCI			7,024
Non-credit portion of other-than-temporary impairment losses recognized in other comprehensive income, net of deferred income tax	(53)	(804)	336	3,026
Changes in HTM Related Net Unrealized Gain			(5,927)
Changes in All Other Net Unrealized Gain			28,544
Changes in Defined Benefit Pension and Post-retirement Plans	702	686	2,187	2,098
Changes in Total Accumulated OCI			25,140
Ending balance, OTTI Related Net Unrealized (Loss) Gain	(4,257)		(4,257)
Ending balance, HTM related Net Unrealized Gain	5,217		5,217
Ending balance, All Other Net Unrealized Gain	75,860		75,860
Ending balance, Defined Benefit Pension and Post-retirement Plans	(44,656)		(44,656)
Ending balance, Total Accumulated OCI	$ 32,164		$ 32,164

The net unrealized holding gain (loss) related to held-to-maturity securities transferred from the available-for-sale category, net of tax.

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Represents total other comprehensive income or loss for the period, net of tax. Includes deferred gains (losses) on qualifying hedges, unrealized holding gains (losses) on investment securities, certain changes in the liability for defined benefit pension plans, the portion of other-than-temporary impairments recognized in other comprehensive income, and translation adjustments.

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Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period.

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The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Total of accumulated other comprehensive loss related to that portion of other than temporary impairment (OTTI) due to factors other than credit losses on debt securities categorized either as available-for-sale or held-to-maturity that an entity does not intend to sell and which it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis of the debt security. The amount represented by this item is net of tax, as applicable.

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The increase (decrease) in accumulated comprehensive income during the period related to pension and other postretirement benefit plans, after tax. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

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Appreciation or loss in value (before reclassification adjustment) of the total of unsold securities during the period being reported on, net of tax. Reclassification adjustments include: (1) the unrealized holding gain (loss), net of tax, at the date of the transfer for a debt security from the held-to-maturity category transferred into the available-for-sale category. Also includes the unrealized gain (loss) at the date of transfer for a debt security from the available-for-sale category transferred into the held-to-maturity category; (2) the unrealized gains (losses) realized upon the sale of securities, after tax; and (3) the unrealized gains (losses) realized upon the write-down of securities, after tax.

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The after-tax amount of other than temporary impairment (OTTI) loss on a debt security, categorized as either Available-for-sale or Held-to-maturity, related to factors other than credit losses when the entity does not intend to sell the security and it is not more likely than not that the entity will be required to sell the security before recovery of its amortized cost basis. This amount, net of applicable taxes, includes the portion attributable to the noncontrolling interest, if any; this amount is also referred to as the amount incurred by the reporting entity or the consolidated entity.

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