Fair Value Measurements (Fair Value Mortgage Loans Held For Sale Disclosures) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Mortgage loans held for sale, amortized cost	$ 34,600		$ 34,600		$ 26,400
Mortgage loans held for sale, measured at fair value	35,200		35,200		26,900
Mortgage loans held for sale, difference between fair value and amortized cost	655		655		$ 543
Mortgage Loans Held for Sale [Member]
Change in fair value under fair value option election	$ 441	$ 322	$ 112	$ 773

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

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- Definition

The face amount of loans that will be sold to other entities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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- Definition

The difference between the fair value and principal amount of mortgage loans held for sale.

+ References

No definition available.

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