Investment Securities - Narrative (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015 security	Dec. 31, 2014 security
Marketable Securities [Abstract]
Securities with unrealized losses	14	29
Number of securities in unrealized loss position greater than 12 months	0	0
Available-for-sale Securities Pledged as Collateral	$ 56.3	$ 54.1
Available-for-sale Securities Pledged as Collateral, Percent of Portfolio	22.00%	19.00%

Available-for-sale Securities Pledged as Collateral, Percent of Portfolio

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- Definition

Number of investment securities with unrealized losses for less than 12 months.

+ References

No definition available.

+ Details

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- Definition

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

+ 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=35738203&loc=d3e5086-111524

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- Details

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