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Benefit Plans - Deferred Compensation Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Jan. 01, 2018
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Interest rate earned on deferred amounts, prime rate first business day of year		5.50%		4.50%
Deferred compensation obligation	$ 4.4		$ 3.8
Annual Salary | Management
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Maximum percentage of compensation allowed to be deferred	80.00%
Deferred Bonus | Management
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Maximum percentage of compensation allowed to be deferred	100.00%

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- Definition

Deferred Compensation Arrangement with Individual, Maximum Elected Deferral by Employee, Percent

+ References

No definition available.

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- Definition

Deferred Compensation Arrangement with Individual, Deferred Interest Earned, Percent

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363

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