Employee Benefit Plans: Funding Status of Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Benefit plan liabilities	$ 144,049		$ 144,049		$ 154,472
Other income (expense), net	(1,193)	$ 580	(703)	$ 55
Pension Plan
Benefit plan liabilities	$ 51,000		$ 51,000		$ 51,000

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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