Long-term Debt - Components of Borrowings, Including Current Portion (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2016
Debt Instrument [Line Items]
Borrowings under term loan agreements		$ 60,400
Unamortized debt discounts		(2,004)
Long-term debt, net of discounts	$ 58,930	58,396
Term Loan Agreement
Debt Instrument [Line Items]
Borrowings under term loan agreements	60,900		$ 45,000
Borrowings Under Term Loan Agreements	60,000	60,000
Paid-in-Kind Interest	853	400
Unamortized debt discounts	(1,923)
Long-term debt, net of discounts	$ 58,930	$ 58,396

Borrowings Under Term Loan Agreements

No definition available.

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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.

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- Definition

Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

Interest paid other than in cash for example by issuing additional debt securities. As a noncash item, it is added to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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