Marketable Securities - Held To Maturity, by Contractual Maturity (Details) $ in Thousands	Mar. 31, 2020 USD ($)
Amortized cost
Total marketable securities held-to-maturity	$ 17,208
Fair value
Total marketable securities held-to-maturity	17,968
Residential mortgage-backed securities
Amortized cost
Due in less than one year	1
Due in one year through five years	599
Due after five years through ten years	929
Due after ten years	15,679
Total marketable securities held-to-maturity	17,208
Fair value
Due in less than one year	1
Due in one year through five years	626
Due after five years through ten years	981
Due after ten years	16,360
Total marketable securities held-to-maturity	$ 17,968

Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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