Pension plan and 401(k) Program - Aggregate Information of Projected Benefit in Excess of Benefit Obligation (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Retirement Benefits [Abstract]
Projected benefit obligation	$ 36,406	$ 30,772
Accumulated benefit obligation	36,149	30,583
Fair value of plan assets	$ 25,911	$ 23,610

No definition available.

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- Definition

Amount of accumulated benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2417-114920

+ Details

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- Definition

Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2417-114920

+ Details

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- Definition

Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

+ Details

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