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Summary of Significant Accounting Policies and Basis of Presentation (Detail) - USD ($) | 3 Months Ended
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Mar. 31, 2019 | Mar. 31, 2018
Basis Of Presentation And Accounting Policies [Line Items] |  |
Operating lease, right of use asset | $ 14,058,000 |
Operating lease, liabilities | 13,510,000 |
Operating Lease Term of 12 Months or Less |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |
Operating lease, right of use asset | 0 |
Operating lease, liabilities | $ 0 |
Maximum |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |
Operating lease, term of contract | 12 months |
Customer Relationship |  |
Basis Of Presentation And Accounting Policies [Line Items] |  |
Amortization of intangible assets |  | $ 2,697,000

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- Definition Lease right of use assets and liabilities original lease term. + References No definition available. + Details
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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