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Allowance for Loan Losses - Average Recorded Investment and Interest Income Recognized for TDR (Details) - TDR Loans - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Average Recorded Investment | $ 1,467,098 | $ 1,180,206 | $ 1,391,167 | $ 1,106,946
Interest Income Recognized | $ 24,639 | $ 19,943 | $ 69,159 | $ 56,509

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- Definition Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524 + Details
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