XML 34 R41.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Asset Retirement Obligations (Tables)
 12 Months Ended
Dec. 31, 2019
Asset Retirement Obligation [Abstract]  
Changes to the asset retirement obligations
The following table summarizes the changes to the ARO balances during 2019 and 2018:
ARO Reconciliation
 
(In millions)
 
 
 
Balance, January 1, 2018
 
$
570

Changes in timing and amount of estimated cash flows
 
203

Liabilities settled
 
(1
)
Accretion
 
40

Balance, December 31, 2018
 
$
812

Liabilities settled
 
(2
)
Accretion
 
46

Balance, December 31, 2019 (1)
 
$
856


(1) Includes $691 million related to TMI-2 classified as held for sale. See Note 15, "Commitments,
Guarantees and Contingencies," for further information.