Securities (Securities by Contractual Maturity) (Details) $ in Thousands	Mar. 31, 2020 USD ($)
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	$ 110,903
Available for sale debt securities maturities 1-5 years amortized cost	339,369
Available for sale debt securities maturities 5-10 years amortized cost	269,847
Available for sale debt securities maturities after 10 years amortized cost	176,316
Available for sale debt securities maturities total amortized cost	896,435
Available for sale debt securities maturities within 1 year fair value	114,238
Available for sale debt securities maturities 1-5 years fair value	349,303
Available for sale debt securities maturities 5-10 years fair value	273,824
Available for sale debt securities maturities after 10 years fair value	180,027
Available for sale debt securities fair value	$ 917,392

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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