Repurchase Agreements (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Assets Sold under Agreements to Repurchase [Line Items]
Securities Sold under Agreements to Repurchase, Fair Value of Collateral	$ 558,500
Securities sold under customer repurchase agreements	540,362	$ 442,956
Available-for-sale Securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities Sold under Agreements to Repurchase, Fair Value of Collateral		477,600
Overnight and continuous | U.S. Treasury
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under customer repurchase agreements		$ 443,000
Overnight and continuous | US Government Agencies Debt Securities [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under customer repurchase agreements	$ 540,400