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Goodwill and Other Amortizing Intangible Assets - Summarized Other Intangible Assets (Detail) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Finite-Lived Intangible Assets [Line Items] |  |
Gross Intangible Assets | $ 21,754 | $ 31,455
Accumulated Amortization | (6,822) | (19,442)
Net Intangible Assets | 14,932 | 12,013
Customer Deposit Intangibles [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Intangible Assets | 19,471 | 30,471
Accumulated Amortization | (6,071) | (18,998)
Net Intangible Assets | 13,400 | 11,473
Customer list intangible |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Intangible Assets | 2,283 | 984
Accumulated Amortization | (751) | (444)
Net Intangible Assets | $ 1,532 | $ 540

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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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