Investment Securities (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Level 1 [Member]
Cash and Cash Equivalents [Line Items]
Cash	$ 6,181	$ 6,697
Maximum [Member]
Cash and Cash Equivalents [Line Items]
Maturities benchmark for determining investment in commercial paper, corporate notes and bonds	2 years

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=118262064&loc=SL116631418-115840

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=118262064&loc=SL116631419-115840

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