Securities - Fair Value and Age of Gross Unrealized Losses of Debt Securities (Details) $ in Thousands	Jun. 30, 2020 USD ($) security	Dec. 31, 2019 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Temporarily Impaired Debt Securities, Less Than 12 Months, Number of Securities \| security	2	20
Temporarily Impaired Debt Securities, Less Than 12 Months, Fair Value	$ 49,991	$ 137,097
Temporarily Impaired Debt Securities, Less Than 12 Months, Unrealized Losses	$ (1)	$ (701)
Temporarily Impaired Debt Securities, 12 Months or More, Number of Securities \| security	0	7
Temporarily Impaired Debt Securities, 12 Months or More, Fair Value	$ 0	$ 27,788
Temporarily Impaired Debt Securities, 12 Months or More, Unrealized Losses	$ 0	$ (252)
Temporarily Impaired Debt Securities, Number of Securities \| security	2	27
Temporarily Impaired Debt Securities, Fair Value, Total	$ 49,991	$ 164,885
Temporarily Impaired Debt Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ (1)	$ (953)
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Temporarily Impaired Debt Securities, Less Than 12 Months, Number of Securities \| security	0	0
Temporarily Impaired Debt Securities, Less Than 12 Months, Fair Value	$ 0	$ 0
Temporarily Impaired Debt Securities, Less Than 12 Months, Unrealized Losses	$ 0	$ 0
Temporarily Impaired Debt Securities, 12 Months or More, Number of Securities \| security	0	0
Temporarily Impaired Debt Securities, 12 Months or More, Fair Value	$ 0	$ 0
Temporarily Impaired Debt Securities, 12 Months or More, Unrealized Losses	$ 0	$ 0
Temporarily Impaired Debt Securities, Number of Securities \| security	0	0
Temporarily Impaired Debt Securities, Fair Value, Total	$ 0	$ 0
Temporarily Impaired Debt Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 0	$ 0
Obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Temporarily Impaired Debt Securities, Less Than 12 Months, Number of Securities \| security	1	3
Temporarily Impaired Debt Securities, Less Than 12 Months, Fair Value	$ 49,990	$ 22,638
Temporarily Impaired Debt Securities, Less Than 12 Months, Unrealized Losses	$ (1)	$ (45)
Temporarily Impaired Debt Securities, 12 Months or More, Number of Securities \| security	0	0
Temporarily Impaired Debt Securities, 12 Months or More, Fair Value	$ 0	$ 0
Temporarily Impaired Debt Securities, 12 Months or More, Unrealized Losses	$ 0	$ 0
Temporarily Impaired Debt Securities, Number of Securities \| security	1	3
Temporarily Impaired Debt Securities, Fair Value, Total	$ 49,990	$ 22,638
Temporarily Impaired Debt Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ (1)	$ (45)
Collateralized mortgage obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Temporarily Impaired Debt Securities, Less Than 12 Months, Number of Securities \| security	1	6
Temporarily Impaired Debt Securities, Less Than 12 Months, Fair Value	$ 1	$ 23,393
Temporarily Impaired Debt Securities, Less Than 12 Months, Unrealized Losses	$ 0	$ (73)
Temporarily Impaired Debt Securities, 12 Months or More, Number of Securities \| security	0	6
Temporarily Impaired Debt Securities, 12 Months or More, Fair Value	$ 0	$ 25,254
Temporarily Impaired Debt Securities, 12 Months or More, Unrealized Losses	$ 0	$ (231)
Temporarily Impaired Debt Securities, Number of Securities \| security	1	12
Temporarily Impaired Debt Securities, Fair Value, Total	$ 1	$ 48,647
Temporarily Impaired Debt Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 0	$ (304)
Residential mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Temporarily Impaired Debt Securities, Less Than 12 Months, Number of Securities \| security	0	1
Temporarily Impaired Debt Securities, Less Than 12 Months, Fair Value	$ 0	$ 982
Temporarily Impaired Debt Securities, Less Than 12 Months, Unrealized Losses	$ 0	$ (2)
Temporarily Impaired Debt Securities, 12 Months or More, Number of Securities \| security	0	1
Temporarily Impaired Debt Securities, 12 Months or More, Fair Value	$ 0	$ 2,534
Temporarily Impaired Debt Securities, 12 Months or More, Unrealized Losses	$ 0	$ (21)
Temporarily Impaired Debt Securities, Number of Securities \| security	0	2
Temporarily Impaired Debt Securities, Fair Value, Total	$ 0	$ 3,516
Temporarily Impaired Debt Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 0	$ (23)
Commercial mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Temporarily Impaired Debt Securities, Less Than 12 Months, Number of Securities \| security	0	9
Temporarily Impaired Debt Securities, Less Than 12 Months, Fair Value	$ 0	$ 90,005
Temporarily Impaired Debt Securities, Less Than 12 Months, Unrealized Losses	$ 0	$ (581)
Temporarily Impaired Debt Securities, 12 Months or More, Number of Securities \| security	0	0
Temporarily Impaired Debt Securities, 12 Months or More, Fair Value	$ 0	$ 0
Temporarily Impaired Debt Securities, 12 Months or More, Unrealized Losses	$ 0	$ 0
Temporarily Impaired Debt Securities, Number of Securities \| security	0	9
Temporarily Impaired Debt Securities, Fair Value, Total	$ 0	$ 90,005
Temporarily Impaired Debt Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 0	$ (581)
Corporate obligations
Debt Securities, Available-for-sale [Line Items]
Temporarily Impaired Debt Securities, Less Than 12 Months, Number of Securities \| security	0	1
Temporarily Impaired Debt Securities, Less Than 12 Months, Fair Value	$ 0	$ 79
Temporarily Impaired Debt Securities, Less Than 12 Months, Unrealized Losses	$ 0	$ 0
Temporarily Impaired Debt Securities, 12 Months or More, Number of Securities \| security	0	0
Temporarily Impaired Debt Securities, 12 Months or More, Fair Value	$ 0	$ 0
Temporarily Impaired Debt Securities, 12 Months or More, Unrealized Losses	$ 0	$ 0
Temporarily Impaired Debt Securities, Number of Securities \| security	0	1
Temporarily Impaired Debt Securities, Fair Value, Total	$ 0	$ 79
Temporarily Impaired Debt Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 0	$ 0
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Temporarily Impaired Debt Securities, Less Than 12 Months, Number of Securities \| security	0	0
Temporarily Impaired Debt Securities, Less Than 12 Months, Fair Value	$ 0	$ 0
Temporarily Impaired Debt Securities, Less Than 12 Months, Unrealized Losses	$ 0	$ 0
Temporarily Impaired Debt Securities, 12 Months or More, Number of Securities \| security	0	0
Temporarily Impaired Debt Securities, 12 Months or More, Fair Value	$ 0	$ 0
Temporarily Impaired Debt Securities, 12 Months or More, Unrealized Losses	$ 0	$ 0
Temporarily Impaired Debt Securities, Number of Securities \| security	0	0
Temporarily Impaired Debt Securities, Fair Value, Total	$ 0	$ 0
Temporarily Impaired Debt Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 0	$ 0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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