Comprehensive Income (Components of Accumulated Other Comprehensive Income) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Comprehensive Income [Abstract]
Beginning balance, OTTI Related Net Unrealized (Loss) Gain			$ (4,593)
Beginning balance, HTM related Net Unrealized Gain (Loss)			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	272	2,352	389	3,830
Changes in HTM Related Net Unrealized Gain (Loss)			(2,228)
Changes in All Other Net Unrealized Gain			14,474
Changes in Defined Benefit Pension and Post-retirement Plans	743	786	1,485	1,412
Changes in Total Accumulated OCI			14,120
Ending balance, OTTI Related Net Unrealized (Loss) Gain	(4,204)		(4,204)
Ending balance, HTM related Net Unrealized Gain (Loss)	8,916		8,916
Ending balance, All Other Net Unrealized Gain	61,790		61,790
Ending balance, Defined Benefit Pension and Post-retirement Plans	(45,358)		(45,358)
Ending balance, Total Accumulated OCI	$ 21,144		$ 21,144

Accumulated appreciation or loss, net of tax, in value of the total of unsold securities at the end of an accounting period, excluding unrealized gain (loss) related to (i) the non-credit portion of other-than-temporary impairment losses on fixed maturity securities and (ii) held-to-maturity securities transferred from the available for sale category.

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- Definition

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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- Definition

The net unrealized gain or (loss) included in accumulated other comprehensive income associated with the non-credit portion of other-than-temporary impairment losses on fixed maturity securities, net of tax.

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- Definition

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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Represents the total change during the period in the accumulated other comprehensive income or loss balance related to held-to-maturity securities transferred from the available-for-sale category recognized in other comprehensive income.

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Non-credit portion of other-than-temporary impairment losses on fixed maturity securities recognized in other comprehensive income, net of deferred income tax. This item includes subsequent changes to these securities such as amortization on HTM securities or subsequent sales. This item does not include subsequent changes in appreciation or loss in value.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 26

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph i

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 7
-Subparagraph c

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at fiscal year-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, and unrealized gains and losses on certain investments in debt and equity securities as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ 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 AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 14, 17, 26

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 31
-Article 5

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- Definition

Net changes to accumulated comprehensive income during the period related to benefit plans, after tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 7
-Subparagraph c

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 14, 17, 22, 26

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- Definition

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 or 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 or 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 or losses realized upon the sale of securities, after tax; and (3) the unrealized gains or losses realized upon the write-down of securities, after tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 17, 22

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 24
-Subparagraph b

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