Stock Based Compensation Restricted Stock Units Granted and Unvested (Details) - 2014 Equity Plan - Restricted Stock Units (RSUs) - Executive Employee	12 Months Ended
Dec. 31, 2020 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSUs granted (in shares)	12,652
Number of unvested RSUs (in shares)	5,639
2019 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSUs granted (in shares)	3,734
Weighted-average grant date fair value (in usd per share) \| $ / shares	$ 47.75
Number of unvested RSUs (in shares)	500
2020 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSUs granted (in shares)	8,918
Weighted-average grant date fair value (in usd per share) \| $ / shares	$ 36.26
Number of unvested RSUs (in shares)	5,139

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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No definition available.

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- Definition

Net number of non-option equity instruments granted to participants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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