Pension Plans (Contributions) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Qualified Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block
Expected amortization defined benefit plan	$ 4,600
Contributions	0	$ 30,000
Expected contributions during 2020(1)	10,000
SERP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block
Expected amortization defined benefit plan	900
Contributions	534	$ 949
Expected contributions during 2020(1)	$ 528

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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