Deposits - Narrative (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Aggregate amount of time deposits in denominations of $250 thousand or more	$ 554,400,000	$ 378,000,000.0
Certificates of Deposit
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Certificate of deposit to secure deposits, carrying value	$ 0	$ 0

Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116652737&loc=d3e64164-112818

Name:	us-gaap_DepositLiabilitiesCollateralIssuedFinancialInstruments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant