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Quality of Loans (Excluding PCI Loans) (Parenthetical) (Detail) - Commercial and Industrial - Taxi Medallion Loans - USD ($) $ in Millions | Jun. 30, 2018 | Dec. 31, 2017
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Financing Receivable, 30-89 Days Past Due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Past Due | $ 2.0 | $ 2.7
Loans 90 Days Or More Past Due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total Past Due | $ 43.5 | $ 46.7

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- Definition Recorded Investment in financing receivables that are past due at the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524 + Details
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