Transfers of Financial Assets (Loans sold) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Servicing Assets at Fair Value [Line Items]
Net gain on sale	$ 9,937	$ 14,635	$ 7,795
Proceeds from loans not originated for sale	14,679	34,170	33,644
Residential Mortgage [Member]
Servicing Assets at Fair Value [Line Items]
Proceeds from sale	335,656	438,925	452,590
Loans sold with servicing rights retained	304,788	399,318	416,277
Net gain on sale	6,211	11,629	7,795
Ancillary Fee Income Generated by Servicing Financial Assets, Amount	2,629	3,532	0
Fair value option adjustment	1,097	(526)	0
Proceeds from loans not originated for sale	7,400	7,600
Commercial Loan [Member]
Servicing Assets at Fair Value [Line Items]
Net gain on sale		2,100
Proceeds from loans not originated for sale	$ 7,200	$ 26,500	700
Consumer Loan [Member]
Servicing Assets at Fair Value [Line Items]
Proceeds from loans not originated for sale			$ 32,900

All amounts that are due to the servicer of a financial asset, excluding contractually specified servicing fees and late fees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122596-111746

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 225
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The carrying amount of mortgage loans on real estate that were sold during the reporting period.

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The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future.

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Amount of cash inflow from loans and leases held-for-investment, classified as other.

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