Unsecured senior notes payable (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Jan. 26, 2026	Apr. 28, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Apr. 30, 2025	Feb. 13, 2025
Debt Instrument [Line Items]
Loss on early extinguishment of debt			$ (107)	$ 0	$ 0
5.50% Unsecured Senior Notes Payable
Debt Instrument [Line Items]
Outstanding Balance			$ 550,000				$ 550,000
Weighted Average Effective Interest Rate							5.50%
Stated interest rate (as a percent)			5.50%
3.45% unsecured senior notes payable
Debt Instrument [Line Items]
Outstanding Balance						$ 600,000
Stated interest rate (as a percent)						3.45%
Loss on early extinguishment of debt		$ 0
4.30% unsecured senior notes payable
Debt Instrument [Line Items]
Outstanding Balance			$ 300,000
Stated interest rate (as a percent)			4.30%
4.30% unsecured senior notes payable | Subsequent Event
Debt Instrument [Line Items]
Outstanding Balance	$ 300,000
Stated interest rate (as a percent)	4.30%
Loss on early extinguishment of debt	$ 0