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Investments in Qualified Affordable Housing Partnerships, Tax Credit and Other Investments, Net (Details 2) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
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Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |  |  |
Investments in tax credit and other investments, net | $ 203,758 |  | $ 203,758 |  | $ 173,280
Noninterest expense — amortization of tax credit and other investments | 23,827 | $ 32,618 | 66,059 | $ 60,779 |
Accrued Expenses and Other Liabilities |  |  |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |  |  |
Total unfunded commitments for investments in tax credit and other investments | $ 103,000 |  | $ 103,000 |  | $ 117,000

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- Definition Represents the net amount of investments in the projects, excluding affordable housing projects, that qualify for Community Reinvestment Act (CRA) credits or other types of tax credits. + References No definition available. + Details
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- Definition [Line Items] for Investments in Tax Credit and Other Investments, Net [Table] + References No definition available. + Details
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- Definition Amortization of investments in projects that qualify for Community Reinvestment Act ("CRA") and other tax credits, included as a component of noninterest expense. + References No definition available. + Details
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- Definition Amount of commitment or contingent commitments to investments in certain limited partnerships that qualify for Community Reinvestment Act (CRA) credits or other types of tax credits. + References No definition available. + Details
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