Amount of available-for-sale debt securities at fair value maturing after one year through two years.

No definition available.

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Amount of available-for-sale debt securities at fair value maturing after three years through five years.

+ References

No definition available.

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Amount of available-for-sale debt securities at fair value maturing after two year through three years.

+ References

No definition available.

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- Definition

Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing after tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

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Investments - Contractual Maturities of Debt Securities and Other Investments (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, Fair Value/Carrying Value	$ 44,873	$ 37,700	$ 37,660
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	2,900
One to two years	3,752
Two to three years	6,122
Three to five years	236
Available-for-sale debt securities, Fair Value/Carrying Value	13,010		9,384
Municipal Fixed-Rate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	737
One to two years	1,183
Two to three years	908
Three to five years	296
Available-for-sale debt securities, Fair Value/Carrying Value	3,124		930
Asset-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	696
One to two years	956
Two to three years	615
Three to five years	4,817
Five to ten years	946
More than ten years	557
Available-for-sale debt securities, Fair Value/Carrying Value	8,587		6,890
Mortgage/Agency-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	208
One to two years	1,256
Two to three years	2,775
Three to five years	1,079
Five to ten years	1,507
More than ten years	4,255
Available-for-sale debt securities, Fair Value/Carrying Value	11,080		6,962
U.S. Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	500
One to two years	826
Two to three years	5,492
Three to five years	452
Available-for-sale debt securities, Fair Value/Carrying Value	7,270		12,323
Foreign Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	75
One to two years	463
Two to three years	497
Available-for-sale debt securities, Fair Value/Carrying Value	1,035		$ 371
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	325
Available-for-sale debt securities, Fair Value/Carrying Value	325
Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	442
Available-for-sale debt securities, Fair Value/Carrying Value	$ 442