Investment Securities - Gross Unrealized Losses and Fair Value, Aggregated by Investment Category (Detail) $ in Thousands	Jun. 30, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Fair Value	$ 4,961
Less than 12 Months, Unrealized Losses	(39)
12 Months or More, Fair Value	0
12 Months or More, Unrealized Losses	0
Fair Value, Total	4,961
Unrealized Losses	(39)
Corporate notes
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Fair Value	4,961
Less than 12 Months, Unrealized Losses	(39)
12 Months or More, Fair Value	0
12 Months or More, Unrealized Losses	0
Fair Value, Total	4,961
Unrealized Losses	$ (39)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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