Accumulated Other Comprehensive Income (Loss) - Schedule Of The Changes In Components Of Accumulated Other Comprehensive Income (Loss) Balances (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 8,201,767	$ 7,215,114	$ 7,723,054	$ 6,950,834
Net unrealized gains (losses) arising during the period	76,479	197,109	187,037	124,771
Amounts reclassified from AOCI	10,344	19,760	22,666	58,521
Other comprehensive income	86,823	216,869	209,703	183,292
Ending balance	8,582,800	7,664,539	8,582,800	7,664,539
Debt Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(466,566)	(591,286)	(542,152)	(601,881)
Net unrealized gains (losses) arising during the period	76,760	132,130	149,063	138,621
Amounts reclassified from AOCI	6,187	2,663	9,470	6,767
Other comprehensive income	82,947	134,793	158,533	145,388
Ending balance	(383,619)	(456,493)	(383,619)	(456,493)
Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	28,622	(44,059)	(20,787)	2,624
Net unrealized gains (losses) arising during the period	(2,355)	66,105	38,015	(15,235)
Amounts reclassified from AOCI	4,157	17,097	13,196	51,754
Other comprehensive income	1,802	83,202	51,211	36,519
Ending balance	30,424	39,143	30,424	39,143
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(24,436)	(18,828)	(22,321)	(21,339)
Net unrealized gains (losses) arising during the period	2,074	(1,126)	(41)	1,385
Amounts reclassified from AOCI	0	0	0	0
Other comprehensive income	2,074	(1,126)	(41)	1,385
Ending balance	(22,362)	(19,954)	(22,362)	(19,954)
AOCI, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(462,380)	(654,173)	(585,260)	(620,596)
Other comprehensive income	86,823	216,869	209,703	183,292
Ending balance	$ (375,557)	$ (437,304)	$ (375,557)	$ (437,304)