Amortized period of line of credit facility cost.

No definition available.

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- Definition

Debt instrument additional basis spread.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility loan cost.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Line of credit facility unamortized loan cost.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of monthly installments.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Stock repurchased during period price per share.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
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Balance Type:	debit
Period Type:	duration

- Definition

Dividend or interest rate associated with the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction. Noncash are transactions that affect recognized assets or liabilities but that do not result in cash receipts or cash payments. Part noncash refers to that portion of the transaction not resulting in cash receipts or cash payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
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+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The name of the original debt issue that has been converted in a noncash (or part noncash) transaction during the accounting period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

+ Details

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Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the required periodic payments applied to principal.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Paragraph 1
-Subparagraph (SX 210.9-03(16))
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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), excluding current portion.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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Bank Loan - Additional Information (Detail)				3 Months Ended
Bank Loan - Additional Information (Detail)	Dec. 01, 2017	Sep. 30, 2017 USD ($)	Sep. 17, 2015 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) Installment	Dec. 31, 2016 USD ($)	Sep. 16, 2015 USD ($)
Debt Instrument [Line Items]
Long-term debt, gross				$ 25,200,000
Long-term debt		$ 25,956,000		$ 24,899,000
US Bank National Association Loan [Member]
Debt Instrument [Line Items]
Number of monthly installments payable \| Installment				48
Required monthly loan principal repayment				$ 364,583
Common stock repurchase, share \| shares			1,500,000
Common stock repurchase, price per share \| $ / shares			$ 16.67
Outstanding bank loan			$ 35,000,000
Long-term loan outstanding principal balance						$ 23,000,000
Final installment date				Sep. 17, 2019
Amortized loan costs				$ 410,000
Amortized cost on straight-line basis in months				48 months
Amortization expenses				$ 40,000	$ 40,000
Unamortized loan cost				$ 300,000
US Bank National Association Loan [Member] \| Promissory Note [Member]
Debt Instrument [Line Items]
Outstanding bank loan			20,000,000
California Bank and Trust Loan [Member] \| Promissory Note [Member]
Debt Instrument [Line Items]
Outstanding bank loan			$ 15,000,000
Prime Rate [Member] \| US Bank National Association Loan [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate				0.50%
One Month Libor [Member] \| US Bank National Association Loan [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate		2.75%		1.00%
Debt instrument converted rate	1.361%
Effective interest rate on debt				4.111%
Debt conversion description				The Company intends to renew the LIBOR rate contract on a monthly basis provided that the LIBOR-based interest rate remains favorable to the prime rate-based interest rate.
Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| US Bank National Association Loan [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate				2.75%
Minimum [Member] \| One Month Libor [Member] \| US Bank National Association Loan [Member]
Debt Instrument [Line Items]
Debt instrument additional basis spread				0.25%
Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| US Bank National Association Loan [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate				3.25%
Maximum [Member] \| One Month Libor [Member] \| US Bank National Association Loan [Member]
Debt Instrument [Line Items]
Debt instrument additional basis spread				0.75%