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Employment period required for plan participation, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Number of shares authorized under the Employee Stock Purchase Plan (ESPP).

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- Definition

Refers to the percentage of employee compensation that can be withheld to purchase common stock.

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No definition available.

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- Definition

The percentage of eligible employees participating in plan.

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No definition available.

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- Definition

The participation periods implemented by the Employee Stock Purchase Plan, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Purchase price of stock as percentage of lower of the fair market value on the last trading day before the date of participation or the fair market value on the last trading day during the participation period.

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No definition available.

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- Definition

Represents the amount of cash contributions during the period made to the Employee Stock Purchase Plan (ESPP).

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No definition available.

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- Definition

The percentage rate used to calculate dividend payments on stock.

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No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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No definition available.

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- Definition

Per share weighted-average price paid for shares purchased on open market for issuance under share-based payment arrangement.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock Compensation Plans, Employee Stock Purchase Plan (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 27, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Subsequent Event [Member]
Employee Stock Purchase Plan [Abstract]
Stock dividend percentage	5.00%
Dividends, date declared	Jan. 27, 2021
Dividends, date to be paid	Mar. 25, 2021
Dividends, date of record	Feb. 26, 2021
2016 Amended Employee Stock Purchase Plan [Member]
Employee Stock Purchase Plan [Abstract]
Shares authorized for issuance under plan (in shares)		325,543
Purchase price of stock in percentage for participation		85.00%
Percentage of eligible employee participating in plan		37.00%
Cash contributions to ESPP		$ 107
Shares purchased for award (in shares)		13,722
Weighted average purchase price of shares purchased (in dollars per share)		$ 7.77
Compensation cost related to ESPP		$ 19	$ 17	$ 22
2016 Amended Employee Stock Purchase Plan [Member] \| Minimum [Member]
Employee Stock Purchase Plan [Abstract]
Eligibility employment period required for plan participation		90 days
2016 Amended Employee Stock Purchase Plan [Member] \| Maximum [Member]
Employee Stock Purchase Plan [Abstract]
Plan participation period		27 months
Percentage of employee compensation that can be withheld to purchase common stock		10.00%