Fair Value - Level 3 Assets (Details) - Level 3 - Available-for-sale securities - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	$ 13,620	$ 6,309	$ 12,577	$ 10,079
Included in earnings	(1)	10	8	1
Included in other comprehensive income	30	(53)	298	(41)
Purchases	0	3,047	2,133	3,047
Sales	(6,932)	(472)	(7,369)	(965)
Transfers into Level 3	5,132	5,370	10,651	7,782
Transfers out of Level 3	(2,925)	(3,091)	(9,374)	(8,783)
Ending balance	8,924	11,120	8,924	11,120
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	11	(53)	184	(28)
Corporate debt securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	11,523	6,309	12,577	7,879
Included in earnings	(20)	10	(9)	1
Included in other comprehensive income	23	(53)	291	(48)
Purchases	0	3,047	734	3,047
Sales	(5,841)	(472)	(6,272)	(965)
Transfers into Level 3	2,581	5,370	7,394	7,782
Transfers out of Level 3	(1,893)	(3,091)	(8,342)	(6,576)
Ending balance	6,373	11,120	6,373	11,120
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	(18)	(53)	158	(28)
Residential mortgage-backed securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	915		0
Included in earnings	4		4
Included in other comprehensive income	15		15
Purchases	0		921
Sales	(26)		(32)
Transfers into Level 3	0		0
Transfers out of Level 3	(908)		(908)
Ending balance	0		0
Commercial mortgage-backed securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	1,182		0
Included in earnings	15		13
Included in other comprehensive income	(8)		(8)
Purchases	0		478
Sales	(1,065)		(1,065)
Transfers into Level 3	2,551		3,257
Transfers out of Level 3	(124)		(124)
Ending balance	2,551		2,551
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	$ 29		$ 26
Collateralized debt obligations
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance				2,200
Included in earnings				0
Included in other comprehensive income				7
Purchases				0
Sales				0
Transfers into Level 3				0
Transfers out of Level 3				(2,207)
Ending balance		$ 0		$ 0

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

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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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-Publisher FASB
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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
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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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