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Servicing Assets - Unpaid Principal Balances of Loans Serviced for Others (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Loan portfolios serviced for: |  |
Unpaid principal balances of loans serviced | $ 1,112,901 | $ 1,017,928
SBA guaranteed loans |  |
Loan portfolios serviced for: |  |
Unpaid principal balances of loans serviced | 1,021,143 | 911,803
USDA guaranteed loans |  |
Loan portfolios serviced for: |  |
Unpaid principal balances of loans serviced | $ 91,758 | $ 106,125

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- Definition This is the result of the principal amount outstanding of total loans managed or securitized less securitized loans and loans that are in the process of being securitized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82924980&loc=d3e107314-111719 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- References No definition available. + Details
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- Details
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Namespace Prefix: |
Data Type: | na
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Period Type: |

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- Details
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