SECURITIES - Total Available for Sale and Held to Maturity Investment Securities by Contractual Maturity (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Fair Value, Total securities
Within One Year	$ 60,803
After One But Within Five Years	71,716
After Five But Within Ten Years	74,715
After Ten Years	566,084
Total Estimated Fair Value	773,318
Amortized Cost, Total securities
Within One Year	60,802
After One But Within Five Years	71,443
After Five But Within Ten	75,743
After Ten Years	565,113
Total Amortized Cost	$ 773,101