Loans Receivable and Allowance for Credit Losses (Summary of Activities in Allowance for Unfunded Credit Reserves) (Details) - Allowance for Unfunded Credit Reserve - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for unfunded credit reserves
Beginning balance	$ 12,566	$ 13,318	$ 16,121
Reversal of unfunded credit commitments	(1,408)	(752)	(2,803)
Ending balance	$ 11,158	$ 12,566	$ 13,318

Amount of expense related to credit loss from transactions other than loan and lease transactions.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(11))
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

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