Fair Value (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) security	Dec. 31, 2019 USD ($) security
Fair Value [Abstract]
Available-For-Sale Securities, Number Of Debt Securities With Unobservable Inputs \| security	1	1
Transfer of assets from level 1 to level 2	$ 0	$ 0
Transfer of assets from level 2 to level 1	0	0
Transfer of liabilities from level 1 to level 2	0	0
Transfer of liabilities from level 2 to level 1	0	0
Transfers into Level 3	0	0
Transfers out of level 3	$ 0	$ 0

Available-For-Sale Securities, Number Of Debt Securities With Unobservable Inputs

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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- Definition

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

+ References

+ Details

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