CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Statement [Abstract]
Consolidated revenue	$ 2,329.6	$ 2,412.4	$ 2,027.5
Consolidated expenses:
Compensation and related expenses	1,071.5	1,047.1	883.7
Selling, general and administrative	385.5	347.1	321.4
Intangible amortization and impairments	51.6	35.7	140.5
Interest expense	114.4	111.4	92.3
Depreciation and other amortization	15.8	16.6	19.1
Other expenses (net)	34.7	73.5	52.8
Total consolidated expenses	1,673.5	1,631.4	1,509.8
Equity method income (loss) (net)	338.1	242.5	(43.4)
BPEA Transaction gain (Note 10)	641.9	0.0	0.0
Investment and other income	110.3	117.6	34.1
Income before income taxes	1,746.4	1,141.1	508.4
Income tax expense	358.3	251.0	81.4
Net income	1,388.1	890.1	427.0
Net income (non-controlling interests)	(242.2)	(324.4)	(224.8)
Net income (controlling interest)	$ 1,145.9	$ 565.7	$ 202.2
Average shares outstanding (basic) (in shares)	38.5	41.5	46.5
Average shares outstanding (diluted) (in shares)	49.0	44.8	46.7
Earnings per share (basic) (in dollars per share)	$ 29.77	$ 13.65	$ 4.34
Earnings per share (diluted) (in dollars per share)	$ 25.35	$ 13.05	$ 4.33

Amortization and Impairments Of Intangible Assets

No definition available.

Name:	amg_AmortizationAndImpairmentsOfIntangibleAssets
Namespace Prefix:	amg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate expense charged against earnings to allocate the cost of tangible assets to periods in which the assets are used and held and to allocate the cost of issuing debt to periods in which the debt is outstanding. As a noncash expense, this element is added back to net income when calculating cash provided by (used in) operations using the indirect method.

+ References

No definition available.