Leases - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Lessee, Lease, Description
Operating lease, liability, including sublease receivables	$ 590,800,000		$ 590,800,000		$ 598,300,000
Operating lease, liability	578,818,000		578,818,000		585,747,000
Operating lease, liability, portion ring-fenced by special purpose vehicles	21,200,000		21,200,000		22,600,000
Operating lease, liability, portion ring-fenced excluding special purpose vehicles	11,000,000.0		11,000,000.0		10,200,000
Operating lease, future contracted revenues and sublease income			175,700,000		$ 158,200,000
Operating lease costs	37,200,000	$ 32,000,000.0	71,000,000.0	$ 65,500,000
Operating lease payments			70,900,000	65,500,000
Short-term lease expense	500,000	0.0	800,000	400,000
Sublease income	1,100,000	900,000	2,000,000.0	1,500,000
Lease impairment	$ 0	0	0	0
Operating lease, right-of-use asset, periodic reduction			$ 13,300,000
Weighted average discount rate	5.15%		5.15%		5.02%
Weighted average lease term	6 years 3 months 18 days		6 years 3 months 18 days		5 years 8 months 12 days
Right-of-use assets	$ 494,982,000		$ 494,982,000		$ 500,464,000
Right-of-use liabilities	$ 106,329,000		$ 106,329,000		$ 108,434,000
Operating lease, liability, current, statement of financial position flag	Accounts payable, accrued expenses and other liabilities (see Note 25)		Accounts payable, accrued expenses and other liabilities (see Note 25)		Accounts payable, accrued expenses and other liabilities (see Note 25)
Right-of-use liabilities, non-current	$ 484,427,000		$ 484,427,000		$ 489,832,000
Rent expense	46,100,000	$ 41,300,000	88,100,000	$ 83,000,000.0
Management Services, Servicing Fees and Other
Lessee, Lease, Description
Operating lease, liability	$ 123,100,000		$ 123,100,000		$ 151,100,000
Minimum
Lessee, Lease, Description
Remaining lease terms	1 year		1 year
Options to extend leases	1 year		1 year
Maximum
Lessee, Lease, Description
Remaining lease terms	17 years		17 years
Options to extend leases	10 years		10 years