Borrowings (Westpac Bank Corporate Credit Facility (NZ)) (Narrative) (Details) $ in Thousands, $ in Millions	9 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2023 NZD ($)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Contractual facility	$ 216,749		$ 227,633
Westpac Bank Corporate Credit Facility [Member]
Debt Instrument [Line Items]
Contractual facility	$ 8,322	$ 13.8	$ 8,777
Maturity date	Jan. 01, 2024	Jan. 01, 2024	Jan. 01, 2024
Interest rate	2.40%	2.40%
Westpac Bank Corporate Credit Facility [Member] | Bank Bill Swap Bid Rate [Member]
Debt Instrument [Line Items]
Interest rate	1.65%	1.65%