Long-term investments - Combined Information for APUC's interest in VIE's (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Variable Interest Entity [Line Items]
Interest income	$ 107,143	$ 101,523
Impairment		0
Other
Variable Interest Entity [Line Items]
Interest income		330
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Carrying amount	122,752	86,202
Development loans receivable	52,923	31,468
Performance guarantees and other commitments on behalf of VIEs	658,224	409,232
APUC's maximum exposure in regard to VIE's	$ 833,899	$ 526,902

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Variable Interest Entities, Commitments on Behalf of VIE

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Amount of net assets (liabilities).

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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