The contingent consideration paid.

No definition available.

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- Definition

Amount classified as assets attributable to disposal group held for sale or disposed of.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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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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-Publisher FASB
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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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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

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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

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No definition available.

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Note 3 - Acquisitions (Details Textual) $ in Thousands		12 Months Ended
Note 3 - Acquisitions (Details Textual) $ in Thousands	Jul. 05, 2018	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Number of Businesses Acquired		12	10
Business Combination, Acquisition Related Costs		$ 11,747	$ 6,247
Business Acquisition, Goodwill, Expected Tax Deductible Amount		379,486	17,531
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		196,480
Finland Residential Property Management Business [Member]
Disposal Group, Including Discontinued Operation, Assets, Total		17,713
Gain (Loss) on Disposition of Business		98
Harrison Street Real Estate Capital [Member]
Number of Businesses Acquired	1
Business Acquisition, Percentage of Voting Interests Acquired	75.00%
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		61,465
Acquisitions after December 31, 2008 [Member]
Business Combination, Contingent Consideration, Liability, Total		93,865
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low		175,870
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High		206,906
Contingent Consideration Paid		19,946	$ 11,187
Acquisitions after December 31, 2008 [Member] \| Contingent Consideration, Compensation Element [Member]
Business Combination, Contingent Consideration, Liability, Total		15,161
Finland Residential Property Management Business [Member]
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		45,364
Other Acquisitions [Member]
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		$ 89,651
Americas [Member]
Number of Businesses Acquired		5
EMEA [Member]
Number of Businesses Acquired		4
Asia Pacific [Member]
Number of Businesses Acquired		2