Securities (Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	$ 103,283
Available for sale debt securities maturities 1-5 years amortized cost	509,654
Available for sale debt securities maturities 5-10 years amortized cost	312,960
Available for sale debt securities maturities after 10 years amortized cost	244,208
Available for sale debt securities maturities total amortized cost	1,170,105	$ 1,166,340
Available for sale debt securities maturities within 1 year fair value	83,196
Available for sale debt securities maturities 1-5 years fair value	422,408
Available for sale debt securities maturities 5-10 years fair value	255,998
Available for sale debt securities maturities after 10 years fair value	197,388
Available for sale debt securities, fair value	$ 958,990	$ 993,928

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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