Consolidated Statements of Cash Flows (Parenthetical) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income taxes paid, net	$ (37,036,000)	$ (36,795,000)	$ (57,726,000)
Restricted stock unit dividend equivalents, net of forfeitures	5,973,000	6,544,000	$ 3,356,000
The Cohen & Steers Preferred Securities and Income SMA Shares [Member]
Transfer of redeemable noncontrolling interest in consolidated entity	7,181,000
SICAV Preferred
Transfer of redeemable noncontrolling interest in consolidated entity	114,192,000
SICAV GRE
Noncontrolling Interest, Increase from Business Combination	$ 45,988,000
Cohen & Steers Funds ICAV [Member]
Transfer of redeemable noncontrolling interest in consolidated entity		$ 6,411,000

Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared and applicable to holders of share-based compensation, for example, but not limited to, non-vested shares, stock options, or restricted stock units.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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The amount of the reduction or elimination during the period of a noncontrolling interest resulting from the parent's loss of control and deconsolidation of the entity in which one or more outside parties had a noncontrolling interest.

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Amount of increase in noncontrolling interest from a business combination.

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