Other Comprehensive (Loss) Income - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Fixed maturity securities	$ 214	$ (228)
Bank loan participations	(45,153)	(1,679)
Net realized and unrealized gains (losses) on investments in equity securities	$ (13,500)	$ 3,500

Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27357-111563

Name:	us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration