Loans Receivable and Allowance for Credit Losses (Loans Held-for-Sale Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Loans Held for Sale
Loans held-for-sale, including loans pending sale	$ 78,200
Branch assets held-for-sale	91,318	$ 0
Loans held-for-sale	85	$ 23,076
Loans held-for-sale
Loans Held for Sale
Branch assets held-for-sale	$ 78,100

Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant