Loans and Allowance for Loan Losses - Loans Pledged (Details) $ in Millions	Mar. 31, 2019 USD ($)
Loans and Allowances for Loan Losses
Amount of loans pledged as collateral to the Federal Home Loan Bank	$ 519.3

The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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