Investment Securities (Narrative) (Details) (USD $)	9 Months Ended
Sep. 30, 2014 securities	Dec. 31, 2013
Investments [Abstract]
Pledged to secure deposits	$ 1,930,000,000	$ 2,330,000,000
Number of investment securities in a loss portion, less than twelve months	10
Number of investment securities in a loss portion, twelve months or longer	50
Other-than-temporary impairment charges	$ 88,000

Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Number of Securities

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- Definition

Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Number of Securities

+ References

No definition available.

+ Details

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5086-111524

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25351-111560

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