Short-Term Borrowings - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Short Term Debt [Line Items]
Short-term borrowings	$ 2,480	$ 6,093
Short-term borrowings, weighted-average interest rate	1.86%	1.89%
Unused lines of credit available for borrowing	$ 17,000	$ 12,900
Maximum
Short Term Debt [Line Items]
Short-term borrowings, annual interest rate	2.13%	1.90%
Minimum
Short Term Debt [Line Items]
Short-term borrowings, annual interest rate	1.70%	1.81%
Maturity Date One
Short Term Debt [Line Items]
Short-term borrowings, maturity date	2017-01	2016-01
Maturity Date Two
Short Term Debt [Line Items]
Short-term borrowings, maturity date	2017-05	2016-02
Maturity Date Three
Short Term Debt [Line Items]
Short-term borrowings, maturity date		2016-05

Debt instrument, maturity, month and year.

No definition available.

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- Definition

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

+ References

+ Details

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ 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

Weighted average interest rate of short-term debt outstanding.

+ References

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- Details

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- Details

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