Securities In An Unrealized Loss Position Securities In An Unrealized Loss Position (Narrative) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Aggregate fair value of securities in a continuous unrealized loss position	$ 2,215,999,000	$ 2,895,204,000
Gross Unrealized Losses	64,198,000	69,142,000
Available For Sale Equity Securities Gross Unrealized Gains	17,102,000	20,314,000
Loans and Leases Receivable, Other, Allowance	2,000,000	3,000,000
Noninvestment Grade Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of Securities	7
Aggregate fair value of securities in a continuous unrealized loss position	75,300,000
Available For Sale Equity Securities Gross Unrealized Gains	13,200,000
Preferred stocks
Schedule of Available-for-sale Securities [Line Items]
Aggregate fair value of securities in a continuous unrealized loss position	26,654,000	49,774,000
Gross Unrealized Losses	3,870,000	4,165,000
Available For Sale Equity Securities Gross Unrealized Gains	17,102,000	8,385,000
Common stocks
Schedule of Available-for-sale Securities [Line Items]
Aggregate fair value of securities in a continuous unrealized loss position	48,645,000	15,929,000
Gross Unrealized Losses	9,383,000	5,453,000
Available For Sale Equity Securities Gross Unrealized Gains	$ 0	$ 11,929,000

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

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The allowance for other loan and lease losses represents the reserve to cover probable credit losses related to specifically identified other loans and leases, as well as probable credit losses inherent in the remainder of the other loan portfolio as of the balance sheet date. For banks, include currently required allocated transfer risk reserves. Include carryover of or adjustments to the allowance for other loan losses in connection with business combinations determined to be appropriate.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Available for Sale Equity Securities Gross Unrealized Gains.

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