Revenue from contracts - Contract balances (Details) - USD ($) $ in Millions |
Mar. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Disaggregation of Revenue [Line Items] | ||
| Fuel reserve fund | $ 0.1 | $ 0.2 |
| Contract assets | 0.0 | 0.0 |
| San Diego Projects | ||
| Disaggregation of Revenue [Line Items] | ||
| Contract liabilities | $ 0.1 | $ 0.1 |
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- Definition The amount of liability under fuel reserve fund. No definition available.
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- Definition Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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. No definition available.
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- Details
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