Fair Value - Level 3 Assets (Details) - Level 3 - Available-for-sale securities - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	$ 12,577	$ 10,079
Included in earnings	5	6
Included in other comprehensive income	141	(302)
Purchases	5,719	6,455
Sales	(8,515)	(2,854)
Transfers into Level 3	18,823	18,232
Transfers out of Level 3	(17,105)	(19,039)
Ending balance	11,645	12,577
Change in unrealized gains or losses included in other comprehensive income related to Level 3 securities held at the reporting date
Change in unrealized gains or losses included in other comprehensive income related to Level 3 securities	68	(554)
Corporate debt securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	12,577	7,879
Included in earnings	10	6
Included in other comprehensive income	146	(312)
Purchases	2,020	5,550
Sales	(7,415)	(2,854)
Transfers into Level 3	11,542	18,232
Transfers out of Level 3	(10,556)	(15,924)
Ending balance	8,324	12,577
Change in unrealized gains or losses included in other comprehensive income related to Level 3 securities held at the reporting date
Change in unrealized gains or losses included in other comprehensive income related to Level 3 securities	38	(554)
Residential mortgage-backed securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	0
Included in earnings	4
Included in other comprehensive income	15
Purchases	921
Sales	(32)
Transfers into Level 3	0
Transfers out of Level 3	(908)
Ending balance	0	0
Commercial mortgage-backed securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	0
Included in earnings	(9)
Included in other comprehensive income	(21)
Purchases	478
Sales	(1,068)
Transfers into Level 3	7,281
Transfers out of Level 3	(3,340)
Ending balance	3,321	0
Change in unrealized gains or losses included in other comprehensive income related to Level 3 securities held at the reporting date
Change in unrealized gains or losses included in other comprehensive income related to Level 3 securities	30	0
Collateralized debt obligations
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	0	2,200
Included in earnings	0	0
Included in other comprehensive income	1	10
Purchases	2,300	905
Sales	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	(2,301)	(3,115)
Ending balance	$ 0	$ 0

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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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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No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

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- Definition

Amount of purchases of financial instrument classified as an asset 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 sale of financial instrument classified as an asset 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 transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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

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