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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
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Mar. 31, 2019 | Mar. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Average Recorded Investment | $ 1,312,729 | $ 1,032,232
Interest Income Recognized | $ 21,566 | $ 17,847

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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=84173941&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=84173941&loc=d3e5258-111524 + Details
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- Definition Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + 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)(3) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 + Details
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