XML 31 R89.htm IDEA: XBRL DOCUMENT v2.4.1.9

Related Party Transactions (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Affiliate Partners
Related Party Transactions
Distributions paid to Affiliate management owners	$ 569.4amg_RelatedPartyTransactionDistributiontoNoncontrollingInterests / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	$ 267.1amg_RelatedPartyTransactionDistributiontoNoncontrollingInterests / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	$ 181.4amg_RelatedPartyTransactionDistributiontoNoncontrollingInterests / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember
Amount paid for affiliate equity interest repurchases	32.6amg_RelatedPartyTransactionAmountPaidforEquityInterests / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	36.9amg_RelatedPartyTransactionAmountPaidforEquityInterests / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	8.0amg_RelatedPartyTransactionAmountPaidforEquityInterests / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember
Amount received for affiliate equity issuances	11.0amg_RelatedPartyTransactionsAmountReceivedforEquityIssuances / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	2.5amg_RelatedPartyTransactionsAmountReceivedforEquityIssuances / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	3.3amg_RelatedPartyTransactionsAmountReceivedforEquityIssuances / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember
Affiliate Partners | Other Assets
Related Party Transactions
Receivables from related parties	20.8us-gaap_DueFromRelatedParties / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherAssetsMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	21.8us-gaap_DueFromRelatedParties / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherAssetsMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember
Notes receivable from related parties	9.7us-gaap_NotesReceivableRelatedParties / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherAssetsMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	6.9us-gaap_NotesReceivableRelatedParties / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherAssetsMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	7.1us-gaap_NotesReceivableRelatedParties / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherAssetsMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember
Affiliate Partners | Other Liabilities
Related Party Transactions
Payable to related parties	88.6us-gaap_DueToRelatedPartiesCurrentAndNoncurrent / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherLiabilitiesMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	56.8us-gaap_DueToRelatedPartiesCurrentAndNoncurrent / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherLiabilitiesMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember
Notes payable to related parties	4.4us-gaap_NotesPayableRelatedPartiesCurrentAndNoncurrent / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherLiabilitiesMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	5.5us-gaap_NotesPayableRelatedPartiesCurrentAndNoncurrent / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherLiabilitiesMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember	23.3us-gaap_NotesPayableRelatedPartiesCurrentAndNoncurrent / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherLiabilitiesMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_AffiliatedEntityMember
Prior Owner | Other Liabilities
Related Party Transactions
Investment partnerships with prior owners	71.6amg_InvestmentPartnershipswithPriorOwners / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherLiabilitiesMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = amg_PriorOwnerMember	72.9amg_InvestmentPartnershipswithPriorOwners / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherLiabilitiesMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = amg_PriorOwnerMember
Prior Owner | Non-Controlling Interests
Related Party Transactions
Investment partnerships with prior owners	$ 13.5amg_InvestmentPartnershipswithPriorOwners / us-gaap_BalanceSheetLocationAxis = us-gaap_NoncontrollingInterestMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = amg_PriorOwnerMember	$ 22.2amg_InvestmentPartnershipswithPriorOwners / us-gaap_BalanceSheetLocationAxis = us-gaap_NoncontrollingInterestMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = amg_PriorOwnerMember

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Investment Partnerships with Prior Owners

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