Fair Value Measurements - Reconciliation of activity for assets and liabilities measured at fair value (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Assets:
Assets - Beginning balance	$ 11,211	$ 10,023
Realized (loss) gain included in earnings	4,933	31
Unrealized gain included in other comprehensive income		131
Purchases of available-for-sale securities		4,030
Reclass fair value asset to cost method	(198)	(3,004)
Migrated to Level 2 valuation	(9,233)
Assets - Ending balance	6,713	11,211
Liabilities:
Liabilities - Beginning balance	66
Realized gain included in earnings	(66)	269
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements		(203)
Liabilities - Ending balance	0	66
Equity Investment Other
Assets:
Assets - Beginning balance	10,931	9,794
Realized (loss) gain included in earnings	0	(20)
Unrealized gain included in other comprehensive income		131
Purchases of available-for-sale securities		4,030
Reclass fair value asset to cost method	(198)	(3,004)
Migrated to Level 2 valuation	(9,233)
Assets - Ending balance	1,500	10,931
Liabilities:
Liabilities - Beginning balance	0
Realized gain included in earnings	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements		0
Liabilities - Ending balance	0	0
Mortgage Banking Derivatives
Assets:
Assets - Beginning balance	280	229
Realized (loss) gain included in earnings	4,933	51
Unrealized gain included in other comprehensive income		0
Purchases of available-for-sale securities		0
Reclass fair value asset to cost method	0	0
Migrated to Level 2 valuation	0
Assets - Ending balance	5,213	280
Liabilities:
Liabilities - Beginning balance	66
Realized gain included in earnings	(66)	269
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements		(203)
Liabilities - Ending balance	$ 0	$ 66

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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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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 settlement 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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- Definition

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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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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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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