Borrowings - Components of Long-term Borrowings (Detail) $ in Thousands	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Less: unamortized discount and debt issuance costs	$ (261)
current portion of long-term borrowings, net	83,479
Exchangeable Senior Notes [Member] \| 5.0% Exchangeable Senior Notes due March 2021 [Member]
Debt Instrument [Line Items]
Long-term borrowings	$ 83,740

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 of unamortized debt discount (premium) and debt issuance costs.

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

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