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Commitments and Contingencies (Tables)
3 Months Ended
Mar. 31, 2022
Environmental Remediation Obligations [Abstract]  
Changes in Reserve for Environmental Remediation and Asset Retirement Obligations

The following table reflects changes in the reserve for environmental remediation and asset retirement obligations:

 

 

 

March 31,

 

 

 

2022

 

 

 

$

 

Balance at beginning of year

 

 

41

 

Additions and other changes

 

 

1

 

Environmental spending

 

 

(1

)

Balance at end of period

 

 

41