Borrowings Securities Sold under Agreement to Repurchase (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Short-term Debt [Line Items]
Securities Sold under Agreements to Repurchase	$ 192,330	$ 155,388
U.S. Treasury securities and obligations of U.S. government corporations & agencies
Short-term Debt [Line Items]
Securities Sold under Agreements to Repurchase	130,893	100,895
Mortgage-backed securities
Short-term Debt [Line Items]
Securities Sold under Agreements to Repurchase	$ 61,437	$ 54,493

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Period Type:	instant