Securities (Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	$ 177,689
Available for sale debt securities maturities 1-5 years amortized cost	410,399
Available for sale debt securities maturities 5-10 years amortized cost	366,885
Available for sale debt securities maturities after 10 years amortized cost	94,071
Available for sale debt securities maturities total amortized cost	1,049,044	$ 881,570
Available for sale debt securities maturities within 1 year fair value	177,731
Available for sale debt securities maturities 1-5 years fair value	410,341
Available for sale debt securities maturities 5-10 years fair value	364,137
Available for sale debt securities maturities after 10 years fair value	93,624
Available for sale debt securities, fair value	$ 1,045,833	$ 894,571

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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