XML 100 R52.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Comprehensive Income (Details 2) (USD $) In Millions, unless otherwise specified | 6 Months Ended
--- | ---
Jun. 30, 2013
Total [Member] |
Components of Accumulated other comprehensive income, net of taxes |
Balance at the beginning of the period | $ 81.3
Other comprehensive income before reclassifications | (40.4)
Amounts reclassified from other comprehensive income | (1.5)
Net other comprehensive income | (41.9)
Balance at the end of the period | 39.4
Foreign Currency Translation Adjustment [Member] |
Components of Accumulated other comprehensive income, net of taxes |
Balance at the beginning of the period | 76.2
Other comprehensive income before reclassifications | (32.5)
Amounts reclassified from other comprehensive income | 0
Net other comprehensive income | (32.5)
Balance at the end of the period | 43.7
Realized and Unrealized Losses on Derivative Securities [Member] |
Components of Accumulated other comprehensive income, net of taxes |
Balance at the beginning of the period | (2.9)
Other comprehensive income before reclassifications | 0.8
Amounts reclassified from other comprehensive income | 0
Net other comprehensive income | 0.8
Balance at the end of the period | (2.1)
Unrealized Gain (Loss) on Investment Securities [Member] |
Components of Accumulated other comprehensive income, net of taxes |
Balance at the beginning of the period | 8.0
Other comprehensive income before reclassifications | (8.7)
Amounts reclassified from other comprehensive income | (1.5)
Net other comprehensive income | (10.2)
Balance at the end of the period | $ (2.2)

X
- Details
Name: | amg_AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward
Namespace Prefix: | amg_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the net of tax amount of other comprehensive income after reclassifications. + References No definition available. + Details
Name: | amg_OtherComprehensiveIncomeLossAfterReclassificationsNetOfTax
Namespace Prefix: | amg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Represents the net of tax amount of other comprehensive income before reclassifications. + References No definition available. + Details
Name: | amg_OtherComprehensiveIncomeLossBeforeReclassificationNetOfTax
Namespace Prefix: | amg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Represents the net of tax amount of the amounts reclassified from other comprehensive income. + References No definition available. + Details
Name: | amg_OtherComprehensiveIncomeLossReclassificationNetOfTax
Namespace Prefix: | amg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e681-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669686-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 -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 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 15D -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 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 14, 17, 26 -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 8: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 + Details
Name: | us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant