Securities (Securities by Contractual Maturity) (Details) $ in Thousands	Sep. 30, 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	$ 103,108
Available for sale debt securities maturities 1-5 years amortized cost	314,187
Available for sale debt securities maturities 5-10 years amortized cost	304,576
Available for sale debt securities maturities after 10 years amortized cost	177,968
Available for sale debt securities maturities total amortized cost	899,839
Available for sale debt securities maturities within 1 year fair value	105,289
Available for sale debt securities maturities 1-5 years fair value	320,191
Available for sale debt securities maturities 5-10 years fair value	307,688
Available for sale debt securities maturities after 10 years fair value	180,682
Available for sale debt securities fair value	$ 913,850

Line items for schedule of Available for Sale and Held to Maturty Securities.

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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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