Note 2 - Summary of Presentation (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Share-Based Payment Arrangement, Expense	$ 27,087	$ 21,853
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	49,299
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value	$ 22,971	16,866
Long-term Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)	10 years
Share-Based Payment Arrangement, Expense	$ 2,656	6,954
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	24,026
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value	6,671
Mortgage Servicing Rights ("MSRs") [Member]
Servicing Asset at Fair Value, Amount	179,858	$ 172,833
Mortgage Servicing Rights (MSR) Impairment (Recovery)	$ 0
Fannie Mae Delegated Underwriting and Servicing (“DUS”) [Member]
Financing Receivable, Originated, Guarantee Performance Percentage	33.33%
Minimum [Member] \| Long-term Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	5 years
Minimum [Member] \| Customer Lists and Relationships [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	4 years
Minimum [Member] \| Investment Management Contracts [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	5 years
Minimum [Member] \| Trademarks and Trade Names [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	2 years
Minimum [Member] \| Franchise Rights [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	2 years
Minimum [Member] \| Management Contracts and Other [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	2 years
Maximum [Member] \| Long-term Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	10 years
Maximum [Member] \| Customer Lists and Relationships [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	20 years
Maximum [Member] \| Investment Management Contracts [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	15 years
Maximum [Member] \| Trademarks and Trade Names [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	10 years
Maximum [Member] \| Franchise Rights [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	15 years
Maximum [Member] \| Management Contracts and Other [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	10 years
Building [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	20 years
Building [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	40 years
Vehicles [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Vehicles [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Furniture and Fixtures [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Furniture and Fixtures [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	10 years
Computer Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Computer Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	7 years
Leasehold Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	1 year
Leasehold Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	10 years

The percentage of originated finance receivable that is performance is guaranteed.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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The adjustment to the carrying value of the rights retained or purchased to service mortgages. These adjustments are made when the estimate of the fair value is changed. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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