Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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

Fair Value - Quantitative and Qualitative Disclosures about Unobservable Inputs (Details) - Level 3 - Available-for-sale securities - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Fair value measurements on a recurring basis, valuation techniques
Fair value, measurement with unobservable inputs	$ 19,439	$ 11,645	$ 13,620	$ 12,577
Fair Value, Measurements, Recurring Basis \| Non-Binding Broker Quote
Fair value measurements on a recurring basis, valuation techniques
Fair value, measurement with unobservable inputs	$ 12,400	$ 1,300