Borrowings - Schedule of Maturities of Our Borrowings (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
2020	$ 4,255
2021	6,881
2022	14,146
2023	13,333
2024	83,940
Total principal payments	122,555
Unamortized discount	(360)
Unamortized debt issuance costs	(450)
Total debt — net carrying amount	$ 121,745	$ 118,899

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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.

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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.

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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.

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