Borrowings (Westpac Bank Corporate Credit Facility (NZ)) (Narrative) (Details) $ in Thousands, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2024 NZD ($)	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Contractual facility	$ 203,510		$ 218,159
Westpac Bank Corporate Credit Facility [Member]
Debt Instrument [Line Items]
Contractual facility	$ 8,286	$ 13.8	$ 8,775
Maturity date	Jan. 01, 2025	Jan. 01, 2025	Jan. 01, 2025
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%