Investments (Available-for-sale Securities) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Gross realized gains on sales of investment securities available for sale	$ 21,425	$ 1,326	$ 55,651	$ 7,045
Gross realized losses on sales of investment securities available for sale	0	190	679	190
Net realized gains on sales of investment securities available for sale	$ 21,425	$ 1,136	$ 54,972	$ 6,855

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

No definition available.

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