XML 51 R36.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Affiliate Equity (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2012
Affiliate Equity |
Schedule of the changes in redeemable non-controlling interests |
Balance as of January 1, 2012 |  | $ | 451.8 |
Issuance of Redeemable non-controlling interest |  |  | 7.0 |
Repurchase of Redeemable non-controlling interest |  |  | (11.2 | )
Changes in redemption value |  |  | 62.0 |
Balance as of March 31, 2012 |  | $ | 509.6 |
Schedule of the effect of changes in the entity's ownership interest in its affiliates on the controlling interest's equity |
|  | For the Three Months Ended March 31, |
--- | --- | --- | ---
|  | 2011 |  | 2012 |
Net income (controlling interest) |  | $ | 39.1 |  | $ | 37.4 |
Increase (decrease) in controlling interest paid-in capital from purchases and sales of Affiliate equity |  |  | 3.8 |  |  | (6.0 | )
Change from Net income (controlling interest) and net transfers with non-controlling interests |  | $ | 42.9 |  | $ | 31.4 |

X
- Definition Represents a schedule of net income (loss) attributable to the entity and net transfers to non-controlling interest. + References No definition available. + Details
Name: | amg_ScheduleOfNetIncomeLossAttributableToEntityAndNetTransfersWithNoncontrollingInterestTableTextBlock
Namespace Prefix: | amg_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RedeemableNoncontrollingInterestAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of redeemable noncontrolling interest (as defined) included in the statement of financial position as either a liability or temporary equity. As of the date of the statement of financial position, such redeemable noncontrolling interest is currently redeemable, as defined, for cash or other assets of the entity at (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number D-98 -Paragraph 43 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number D-98 -Paragraph 44 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number D-98 -Paragraph 40 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 25 -Appendix A Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number D-98 -Paragraph 41 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number D-98 -Paragraph 42 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
Name: | us-gaap_RedeemableNoncontrollingInterestTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration