CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
NEWMARK Group Inc Parent
Reduction for dividends on preferred stock or units	$ 6.2	$ 9.8

The amount of preferred stock dividends that is an adjustment to net income apportioned to common stockholders.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration