Consolidated Balance Sheets (Parentheticals) $ in Thousands	Dec. 31, 2020 USD ($)
Debt securities, held to maturity, allowance for credit losses	$ 569

Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity), classified as noncurrent.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

Name:	us-gaap_DebtSecuritiesHeldToMaturityAllowanceForCreditLossNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant