Securities (Securities by Contractual Maturity) (Details) $ in Thousands	Mar. 31, 2021 USD ($)
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	$ 167,840
Available for sale debt securities maturities 1-5 years amortized cost	378,248
Available for sale debt securities maturities 5-10 years amortized cost	332,266
Available for sale debt securities maturities after 10 years amortized cost	74,264
Available for sale debt securities maturities total amortized cost	952,618
Available for sale debt securities maturities within 1 year fair value	168,061
Available for sale debt securities maturities 1-5 years fair value	378,259
Available for sale debt securities maturities 5-10 years fair value	328,056
Available for sale debt securities maturities after 10 years fair value	73,718
Available for sale debt securities fair value	$ 948,094

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

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