Investment in Securities (Schedule of Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Amortized Cost, Due in 1 year or less	$ 35,337
Amortized Cost, Due after 1 year through 5 years	106,384
Amortized Cost, Due after 5 years through 10 years	230,729
Amortized Cost, Due after 10 years	41,189
Amortized Cost, Total	413,639
Fair Value, Due in 1 year or less	35,489
Fair Value, Due after 1 year through 5 years	108,511
Fair Value, Due after 5 years through 10 years	242,078
Fair Value, Due after 10 years	41,513
Fair Value, Total	$ 427,591	$ 441,534

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

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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 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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