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Long Term Debt - SVB Loan Agreement - Additional Information (Detail) - SVB Loan Agreement [Member] - USD ($) $ in Thousands	1 Months Ended		3 Months Ended
	Oct. 31, 2018	Oct. 31, 2016	Mar. 31, 2019	Oct. 19, 2018	Jun. 30, 2017
Schedule Of Long Term Debt [Line Items]
Debt instrument variable percentage		5.50%
Debt instrument description			Borrowings under the SVB Loan Agreement bore interest at a variable rate equal to 5.5% plus the greater of (i) 3.5% or (ii) The Wall Street Journal prime rate.
Repayment of outstanding loan principal	$ 4,333
Repayments portion of total borrowing	270
Debt instrument prepayment premium	87
Debt instrument accrued interest	23
Gains losses on extinguishment of debt	229
Reacquisition price of borrowing	4,713
Debt instrument carrying value	$ 4,484
Debt instrument stated percentage				10.75%
Minimum [Member]
Schedule Of Long Term Debt [Line Items]
Debt instrument variable percentage		3.50%
Term Loan A [Member]
Schedule Of Long Term Debt [Line Items]
Maximum term loan borrowing capacity					$ 6,000

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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))
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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Debt Instrument Carrying Value

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Debt Instrument, Prepayment Premium

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Reacquisition price of borrowing.

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Repayment of debt final payment.

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Schedule Of Long Term Debt [Line Items]

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