Investment Securities - Cost and Equity Method Investments (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jul. 01, 2018
Investment [Line Items]
Federal home loan bank stock	$ 30,060,000	$ 43,388,000
Federal reserve bank stock	14,653,000	8,225,000
Equity Securities, FV-NI	1,993,000	1,649,000
Equity Securities without Readily Determinable Fair Value, Amount	2,689,000	2,589,000
Alternative Investment	20,411,000	17,065,000
Other Investments and Securities, at Cost	$ 69,806,000	$ 72,916,000
equity investment shares sold	123,472	66,980,000
Proceeds from Sale of Federal Home Loan Bank Stock	$ 13,300,000	$ 6,700,000
equity investment purchased, shares	128,553
Gain on equity securities, net	$ 5,118,000	4,616,000	$ 1,210,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Percentage				8.55%
Alternative Investment, income recognized	4,800,000	1,400,000
securities purchased [Member]
Investment [Line Items]
Federal reserve bank stock	6,400,000
Investments [Member]
Investment [Line Items]
Gain on equity securities, net	$ 345,000
Common Stock [Member]
Investment [Line Items]
Gain on equity securities, net		287,000
Equity securities
Investment [Line Items]
Equity Securities, FV-NI, Unrealized Gain		$ 3,500,000