Securities (Securities by Contractual Maturity) (Details) $ in Thousands	Sep. 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	$ 105,671
Available for sale debt securities maturities 1-5 years amortized cost	340,179
Available for sale debt securities maturities 5-10 years amortized cost	289,520
Available for sale debt securities maturities after 10 years amortized cost	147,495
Available for sale debt securities maturities total amortized cost	882,865
Available for sale debt securities maturities within 1 year fair value	106,401
Available for sale debt securities maturities 1-5 years fair value	342,582
Available for sale debt securities maturities 5-10 years fair value	290,083
Available for sale debt securities maturities after 10 years fair value	147,954
Available for sale debt securities fair value	$ 887,020

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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