Securities - Unrealized and Realized Gain (Loss) Recognized in Net Income on Equity Investments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Investments, All Other Investments [Abstract]
Net (losses) gains recognized during the period on equity investments	$ (28)	$ (232)	$ (118)	$ (178)
Less: Net gains recognized during the period on equity investments sold during the period	0	0	0	0
Unrealized (losses) gains recognized during the reporting period on equity investments held at the reporting date	$ (28)	$ (232)	$ (118)	$ (178)

The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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