Loans Receivable and Allowance for Credit Losses (Summary of Activities in Allowance for loan losses by Portfolio Segments and Unfunded Credit Commitments) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Allowance for unfunded credit reserves
Allowance for unfunded credit commitments, beginning of period	$ 27,500
Provision for credit losses	8,000	$ 0
Allowance for unfunded credit commitments, end of period	23,200
Unfunded Credit Commitments
Allowance for unfunded credit reserves
Allowance for unfunded credit commitments, beginning of period	27,514	33,577
Allowance for unfunded credit commitments, end of period	23,262	32,529
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	$ (4,252)	$ (1,048)

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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=120399700&loc=SL114874048-224260

Reference 3: 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=123570139&loc=d3e3602-108585

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