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Investments in Qualified Affordable Housing Partnerships, Tax Credit and Other Investments, Net (Investments in Tax Credit and Other Investments, Net) (Details) - USD ($) $ in Thousands | 3 Months Ended |
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Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Investments in tax credit and other investments, net | $ 246,183 |  | $ 224,551
Marketable equity securities |  |  | 31,900
Unrealized loss recognized on marketable equity securities held | (454) |  |
Noninterest expense — amortization of tax credit and other investments | 17,400 | $ 14,360 |
Investments in tax credit and other investments, net |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Marketable equity securities | 31,000 |  |
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 | $ 107,800 |  | $ 113,400

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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 For an unclassified balance sheet, this item represents investments in common and preferred stocks and other forms of securities that provide ownership interests in a corporation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(b)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition The aggregate net change in the difference between the fair value and the carrying value, or in the comparative fair values, of marketable securities categorized as trading held at each balance sheet date, that was included in earnings for the period, which may have arisen from (a) securities classified as trading, (b) the unrealized holding gain (loss) on held-to-maturity securities transferred to the trading security category, and (c) the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) on available-for-sale securities transferred to trading securities during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27405-111563 + Details
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