The contingent consideration paid.

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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- Definition

For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

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- Definition

The number of states the entity operates in as of the balance sheet date.

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No definition available.

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Value of input used to measure servicing asset.

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Note 4 - Acquisitions (Details Textual) $ in Thousands		1 Months Ended	12 Months Ended
Note 4 - Acquisitions (Details Textual) $ in Thousands	May 29, 2020	May 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jul. 13, 2020
Number of Businesses Acquired				4
Servicing Asset at Fair Value, Amount, Ending Balance			$ 108,315
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)			8 years 36 days
Business Acquisition, Goodwill, Expected Tax Deductible Amount			$ 61,146	$ 12,816
Measurement Input, Discount Rate [Member]
Servicing Asset, Measurement Input			0.115
Measurement Input, Prepayment Rate [Member]
Servicing Asset, Measurement Input			0.06
Servicing Contracts [Member]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)			8 years 73 days
Americas [Member]
Number of Businesses Acquired				2
EMEA [Member]
Number of Businesses Acquired				1
Asia Pacific [Member]
Number of Businesses Acquired				1
Dougherty Financial Group LLC [Member]
Number of States in which Entity Operates	21
Maser Consulting P.A. [Member]
Number of States in which Entity Operates					13
Dougherty Financial Group LLC [Member]
Number of Businesses Acquired	4
Colliers Mortgage [Member]
Servicing Asset at Fair Value, Amount, Ending Balance		$ 99,900
Colliers Mortgage [Member] \| Measurement Input, Discount Rate [Member]
Servicing Asset, Measurement Input		0.112
Colliers Mortgage [Member] \| Measurement Input, Prepayment Rate [Member]
Servicing Asset, Measurement Input		0.063
Colliers Mortgage [Member] \| Servicing Contracts [Member]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)		8 years 54 days
Colliers Mortgage [Member] \| Americas [Member]
Number of Businesses Acquired			2
Acquisitions after December 31, 2008 [Member]
Business Combination, Contingent Consideration, Liability, Total			$ 115,643	$ 84,992
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low			184,660
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High			208,610
Contingent Consideration Paid			29,405	23,962
Acquisitions after December 31, 2008 [Member] \| Contingent Consideration, Compensation Element [Member]
Business Combination, Contingent Consideration, Liability, Total			$ 17,646	$ 23,014