Benefit obligations in excess of plan assets (Details 2) - Underfunded Plan - Qualified Plan - Pension Benefits - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 421,166	$ 391,602
Accumulated benefit obligation	421,166	391,602
Fair value of plan assets	$ 365,264	$ 307,809

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

+ References

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-Publisher FASB
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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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

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