Long-Term Debt - Long-term debt and lease financing obligations (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Disclosure [Abstract]
Term loans payable	$ 47,844	$ 41,487
Lease financing obligations	58	284
Total long-term debt and lease financing obligations	47,902	41,771
Unamortized debt issuance costs	(478)	(545)
Current portion of lease financing obligations	(58)	(226)
Long-term debt and lease financing obligations, net of debt issuance costs and current portion	$ 47,366	$ 41,000

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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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
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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

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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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