Securities (Securities by Contractual Maturity) (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	$ 74,364
Available for sale debt securities maturities 1-5 years amortized cost	345,082
Available for sale debt securities maturities 5-10 years amortized cost	351,603
Available for sale debt securities maturities after 10 years amortized cost	231,336
Available for sale debt securities maturities total amortized cost	1,002,385
Available for sale debt securities maturities within 1 year fair value	73,944
Available for sale debt securities maturities 1-5 years fair value	343,090
Available for sale debt securities maturities 5-10 years fair value	348,484
Available for sale debt securities maturities after 10 years fair value	229,363
Available for sale debt securities fair value	$ 994,881

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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