Significant Accounting Policies - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	$ 86,559,000	$ 108,830,000
Client deposit held	$ 7,500,000,000	8,600,000,000
Lease terms	10 years
Debt agreement term	10 years
Line of credit debt issuance costs	$ 11,100,000	9,500,000
Business promotion and advertising costs	85,100,000	68,900,000	$ 57,200,000
Estimated fair value of mortgage servicing rights	1,100,000,000	891,000,000
Mortgage servicing rights, impairment charges	$ 0	0
Ancillary Fee Income, Servicing Financial Asset, Statement of Income or Comprehensive Income [Extensible Enumeration]	Revenue
Revenue	$ 30,173,752,000	26,950,366,000	23,170,119,000
Prepayment fees/late fees/ancillary income earned from loans servicing	22,700,000	41,700,000	11,000,000
Reserve for claims insurance programs	167,900,000	153,400,000
Reserve for claims insurance programs, current	$ 3,000,000	$ 2,200,000
Redeemed common stock (in shares)	311,014,160	332,875,959
Servicing fees
Summary Of Significant Accounting Policies [Line Items]
Revenue	$ 309,500,000	$ 288,000,000	$ 212,900,000
Wholly Owned Property
Summary Of Significant Accounting Policies [Line Items]
Ownership interest in property	100.00%
Commercial Real Estate
Summary Of Significant Accounting Policies [Line Items]
Ownership interest in property	0.00%
Enterprise software development platforms
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful life	3 years
Minimum | Enterprise software development platforms
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful life	3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful life	10 years
Maximum | Buildings and Improvements
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful life	39 years
Maximum | Land Improvements
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful life	15 years
Maximum | Enterprise software development platforms
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful life	7 years
Maximum | Goodwill and other intangible assets
Summary Of Significant Accounting Policies [Line Items]
Intangible assets, estimated useful life	20 years