Securities (Securities by Contractual Maturity) (Details) $ in Thousands	Jun. 30, 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	$ 106,685
Available for sale debt securities maturities 1-5 years amortized cost	361,981
Available for sale debt securities maturities 5-10 years amortized cost	334,575
Available for sale debt securities maturities after 10 years amortized cost	165,543
Available for sale debt securities maturities total amortized cost	968,784
Available for sale debt securities maturities within 1 year fair value	106,963
Available for sale debt securities maturities 1-5 years fair value	362,982
Available for sale debt securities maturities 5-10 years fair value	334,065
Available for sale debt securities maturities after 10 years fair value	165,158
Available for sale debt securities fair value	$ 969,168

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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