Borrowed Funds - Summary of Borrowed Funds (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Securities sold under agreements to repurchase	$ 103,515	$ 121,079
FHLB advances	1,395,243	785,000
Total borrowed funds	1,658,758	906,079
Federal Funds Purchased	$ 160,000	$ 0

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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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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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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