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Notes Payable to Former Stockholders - Additional Information (Detail) - USD ($) $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2019 | Sep. 30, 2018
Restricted Stock - Notes Payable [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured notes interest rate | 5.00% |
Unsecured notes maturity date | Jun. 30, 2020 |
SARs - Notes Payable [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured notes interest rate | 5.00% |
Unsecured notes maturity date | Jun. 30, 2020 |
Notes Payable To Former Stockholders [Member] |  |
Debt Instrument [Line Items] |  |
Principal and interest payments on notes payable to former stockholders | $ 1.5 | $ 1.5

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- Definition Date when the notes payable to former stockholders is scheduled to be fully repaid. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of the required periodic payments including both interest and principal payments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
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- Definition The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Details
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