Employee Benefit Plans (Funded Status) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Funded status
Funded status at end of year	$ (97)	$ (77)
Net amount recognized in balance sheet	(97)	(77)
Amounts recognized in balance sheet consisting of:
Current liabilities	(1)	(1)
Noncurrent liabilities	(96)	(76)
Net amount recognized in balance sheet	(97)	(77)
Other Plan Benefits
Funded status
Funded status at end of year	(21)	(19)
Net amount recognized in balance sheet	(21)	(19)
Amounts recognized in balance sheet consisting of:
Current liabilities	(1)	(1)
Noncurrent liabilities	(20)	(18)
Net amount recognized in balance sheet	(21)	(19)
IMTT \| DB Plans Benefits
Funded status
Funded status at end of year	(74)	(55)
Net amount recognized in balance sheet	(74)	(55)
Amounts recognized in balance sheet consisting of:
Current liabilities	0	0
Noncurrent liabilities	(74)	(55)
Net amount recognized in balance sheet	(74)	(55)
Hawaii Gas Business \| MIC Hawaii \| DB Plans Benefits
Funded status
Funded status at end of year	(2)	(3)
Net amount recognized in balance sheet	(2)	(3)
Amounts recognized in balance sheet consisting of:
Current liabilities	0	0
Noncurrent liabilities	(2)	(3)
Net amount recognized in balance sheet	$ (2)	$ (3)

Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as current. Excludes other postretirement benefit plan.

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

+ References

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Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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