Fair Value - Changes in Fair Value Levels and in Level 3 Liabilities (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Fair value
Asset transfers out of Level 1 into Level 2	$ 0		$ 0
Asset transfers out of Level 2 into Level 1	0		0
Asset transfers into (out of) Level 3			0
Liability transfers out of Level 1 into Level 2	0		0
Liability transfers out of Level 2 into Level 1	0		0
Liability transfers into (out of) Level 3	0		0
Visa derivative \| Funding Swap (Visa Derivative)
Changes in Level 3 liabilities measured at fair value on a recurring basis
Balance	(2,095,000)	$ (1,179,000)	(4,233,000)	$ (2,607,000)
Total net gains (losses) included in other noninterest income	22,000	(417,000)	131,000	(659,000)
Settlements	1,153,000	1,012,000	3,182,000	2,682,000
Balance	(920,000)	(584,000)	(920,000)	(584,000)
Total net gains (losses) included in net income attributable to the change in unrealized gains or losses related to liabilities still held as of September 30,	$ 22,000	$ (417,000)	$ 131,000	$ (659,000)

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of unrealized gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3) and still held.

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-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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