Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- References

No definition available.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Long-term debt - Schedule of Long-Term Debt and Maturities (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Less unamortized debt issuance costs		$ (2,350,000)	$ (2,599,000)
Long-term debt, net—other than bank		1,964,365,000	1,879,641,000
Aggregate principal payments, fiscal year maturity:
2020		102,000,000
2021		54,000,000
2022		213,000,000
2023		154,000,000
2024		5,000,000
Hawaiian Electric Company, Inc. and Subsidiaries
Debt Instrument [Line Items]
Gross long-term debt		1,505,000,000	1,426,546,000
Aggregate principal payments, fiscal year maturity:
2020		96,000,000
2021		0
2022		52,000,000
2023		100,000,000
2024		0
Special purpose revenue bonds issued on behalf of electric utility subsidiaries
Debt Instrument [Line Items]
Long-term debt, net—other than bank		1,497,667,000	1,418,802,000
Senior notes \| Hawaiian Electric Company, Inc. and Subsidiaries
Debt Instrument [Line Items]
Gross long-term debt		963,000,000	913,000,000
Senior notes \| HEI 2.99% term loan, due 2022
Debt Instrument [Line Items]
Gross long-term debt		150,000,000	150,000,000
Senior notes \| HEI 5.67% senior notes, due 2021
Debt Instrument [Line Items]
Gross long-term debt		$ 50,000,000	50,000,000
Debt instrument, stated interest rate		5.67%
Senior notes \| HEI 3.99% senior notes, due 2023
Debt Instrument [Line Items]
Gross long-term debt		$ 50,000,000	50,000,000
Debt instrument, stated interest rate		3.99%
Senior notes \| HEI 4.58% senior notes, due 2025
Debt Instrument [Line Items]
Debt instrument, stated interest rate		4.58%
Senior notes \| HEI 4.72% senior notes, due 2028
Debt Instrument [Line Items]
Debt instrument, stated interest rate		4.72%
Senior notes \| Hamakua Energy 4.02% notes, due 2030, secured by real and personal property of Hamakua Energy, LLC
Debt Instrument [Line Items]
Gross long-term debt		$ 59,699,000	63,438,000
Debt instrument, stated interest rate		4.02%
Term loan \| Hawaiian Electric Company, Inc. and Subsidiaries
Debt Instrument [Line Items]
Gross long-term debt		$ 542,000,000	462,000,000
Term loan \| HEI 2.99% term loan, due 2022
Debt Instrument [Line Items]
Debt instrument, stated interest rate		2.99%
Term loan \| HEI 4.58% senior notes, due 2025
Debt Instrument [Line Items]
Gross long-term debt		$ 50,000,000	50,000,000
Term loan \| HEI 4.72% senior notes, due 2028
Debt Instrument [Line Items]
Gross long-term debt		100,000,000	100,000,000
Unsecured Debt \| Hawaiian Electric Company, Inc. and Subsidiaries
Debt Instrument [Line Items]
Gross long-term debt		963,000,000	964,546,000
Unsecured Debt \| Mauo Unsecured Loan Due 2022
Debt Instrument [Line Items]
Gross long-term debt		$ 9,349,000	$ 0
Aggregate principal payments, fiscal year maturity:
Debt instrument, face amount	$ 50,500,000
Line of credit facility basis point spread		1.375%
Unsecured Debt \| Mauo Unsecured Loan Due 2022 \| LIBOR
Aggregate principal payments, fiscal year maturity:
Line of credit facility basis point spread	1.375%