Other assets - Schedule of Other Assets by Major Categories (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Net deferred tax assets (net of valuation allowance)	$ 794,693	$ 814,265
Investments under the equity method	295,281	261,687
Prepaid taxes	62,549	42,762
Other prepaid expenses	32,527	25,542
Net Carrying Value	189,159	183,381
Derivative assets	28,516	27,913
Trades receivable from brokers and counterparties	7,628	245
Principal, interest and escrow servicing advances	23,818	30,252
Guaranteed mortgage loan claims receivable	4,430	9,184
Operating ROU assets	99,825	95,234
Finance ROU assets	23,567	23,686
Assets for pension benefit	40,836	38,157
Others	159,392	153,669
Total other assets	$ 1,762,221	$ 1,705,977
Operating Lease Right Of Use Asset Statement Of Financial Position	Total other assets	Total other assets
Finance Lease Right Of Use Asset Statement Of Financial Position	Total other assets	Total other assets
Intangible Asset, Finite-Lived
Net Carrying Value	$ 189,159	$ 183,381