XML 63 R44.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Goodwill and Acquired Client Relationships (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract] |
Schedule of Changes in Goodwill | The following tables present the change in Goodwill and components of Acquired client relationships, net of the Company’s consolidated Affiliates:
|  | Goodwill
|  | Institutional |  | Mutual Fund |  | High Net Worth |  | Total
Balance, as of December 31, 2014 |  | $ | 1,159.1 |  |  | $ | 1,125.3 |  |  | $ | 368.4 |  |  | $ | 2,652.8 |
Goodwill acquired |  | 9.2 |  |  | — |  |  | 55.1 |  |  | 64.3 |
Foreign currency translation |  | (27.0 | ) |  | (5.8 | ) |  | (15.9 | ) |  | (48.7 | )
Balance, as of December 31, 2015 |  | $ | 1,141.3 |  |  | $ | 1,119.5 |  |  | $ | 407.6 |  |  | $ | 2,668.4 |
Goodwill acquired |  | — |  |  | — |  |  | — |  |  | — |
Foreign currency translation |  | (5.1 | ) |  | (37.0 | ) |  | 1.8 |  |  | (40.3 | )
Balance, as of December 31, 2016 |  | $ | 1,136.2 |  |  | $ | 1,082.5 |  |  | $ | 409.4 |  |  | $ | 2,628.1 |
Schedule of Changes in, and the Components of, Acquired Client Relationships |
|  | Acquired Client Relationships
|  | Definite-lived |  | Indefinite-lived |  | Total
|  | Gross Book Value |  | Accumulated Amortization |  | Net Book Value |  | Net Book Value |  | Net Book Value
Balance, as of December 31, 2014 |  | $ | 1,255.1 |  |  | $ | (565.0 | ) |  | $ | 690.1 |  |  | $ | 1,088.3 |  |  | $ | 1,778.4 |
New Investments |  | 52.5 |  |  | — |  |  | 52.5 |  |  | — |  |  | 52.5 |
Intangible amortization and impairments |  | — |  |  | (115.4 | ) |  | (115.4 | ) |  | — |  |  | (115.4 | )
Foreign currency translation |  | (5.8 | ) |  | — |  |  | (5.8 | ) |  | (23.3 | ) |  | (29.1 | )
Balance, as of December 31, 2015 |  | $ | 1,301.8 |  |  | $ | (680.4 | ) |  | $ | 621.4 |  |  | $ | 1,065.0 |  |  | $ | 1,686.4 |
New Investments |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Intangible amortization and impairments |  | — |  |  | (107.7 | ) |  | (107.7 | ) |  | (2.5 | ) |  | (110.2 | )
Foreign currency translation |  | (11.8 | ) |  | — |  |  | (11.8 | ) |  | (67.0 | ) |  | (78.8 | )
Balance, as of December 31, 2016 |  | $ | 1,290.0 |  |  | $ | (788.1 | ) |  | $ | 501.9 |  |  | $ | 995.5 |  |  | $ | 1,497.4 |

X
- Definition Tabular disclosure of intangibles assets, in total and by major class, including the gross carrying amount and accumulated amortization. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company. + References No definition available. + Details
Name: | amg_ScheduleOfIntangibleAssetsByMajorClassTableTextBlock
Namespace Prefix: | amg_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267 + Details
Name: | us-gaap_ScheduleOfGoodwillTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration