Loans (Troubled Debt Restructurings Subsequent Default) (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 loan	Dec. 31, 2016 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0	13
Payment Default [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0	7
Recorded Investment on Modifications with Subsequent Default \| $		$ 1.6

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.

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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