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Deposits - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016
Banking and Thrift [Abstract] |  |  |  |  |
Stable interest-bearing deposits, total | $ 5,500.0 |  | $ 5,500.0 |  |
Brokered deposit placement fee | 2.5 | $ 2.6 | 6.8 | $ 7.8 |
Third party broker fees paid | 4.4 | $ 1.1 | 9.7 | $ 4.0 |
Deposits exceeding FDIC insurance limits | 422.4 |  | 422.4 |  | $ 304.5
Accrued interest on deposits | $ 28.2 |  | $ 28.2 |  | $ 18.9

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- Definition Stable Interest-bearing Deposits, Total + References No definition available. + Details
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- Definition Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e7018-107765 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6935-107765 + Details
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- Definition Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 3 -Section V -Paragraph D-E + Details
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