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Business Description And Significant Accounting Policies: Investments (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Sep. 30, 2019
Mar. 31, 2019
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Feb. 28, 2019
Investment [Line Items]            
Assets Held For Sale Used to Acquire Other Investments           $ 28,000
Discount Rate Used in Valuation of Fair Value of Oil and Gas Reserve Quantities 10.00%          
Impairment of investment $ 20,000 $ 6,900 $ 6,859 $ 19,741 $ 0  
Investments     15,810 21,929    
Balance Sheet Reclassification from Investments to Other Assets, Non-current       22,000    
Investment in privately held oil and gas company            
Investment [Line Items]            
Investments     1,500 8,359    
Cash surrender value of life insurance contracts            
Investment [Line Items]            
Investments     13,628 13,056    
Other investments            
Investment [Line Items]            
Investments     $ 682 $ 514