Fair Value Measurements (Details Textuals) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Fair Value Measurements (Textuals) [Abstract]
Other real estate owned measured at fair value	$ 3	$ 21
Write down of Other Real Estate Owned	1	2
Commitment on standby letters of credit	$ 323	$ 353
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgage derivative interest rate lock commitments closing ratio	91.00%
Mortgage servicing rights (MSR) weighted average constant prepayment rate	12.30%
Weighted average discount rate	9.60%
Maximum [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Weighted average discount rate	20.00%
Minimum [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Weighted average discount rate	10.00%

Represents the percentage of loans currently in a lock position which management estimates will ultimately close.

No definition available.

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- Definition

Other real estate owned fair value disclosure.

+ References

No definition available.

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of a securitization, asset-backed financing arrangement, or similar transfer regardless of when the transfer occurred.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=d3e107314-111719

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- Definition

Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)(2)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=d3e107314-111719

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Amount of write-down or reserve recognized in the income statement on real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 970

-SubTopic 360

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-28.FN5)

-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule III)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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