Nature of Operations and Summary of Significant Accounting Policies (Details) - USD ($)	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Cash and cash equivalents held at the Federal Reserve Bank of Kansas City	$ 176,000,000
Required reserve	0
Loans reviewed on a collective basis	4,493,114,000		$ 3,861,707,000
Performing | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans reviewed on a collective basis	224,352,000	$ 200,000,000	$ 47,221,000
London Interbank Offered Rate (LIBOR)
Financing Receivable, Credit Quality Indicator [Line Items]
Loans tied to LIBOR	$ 1,000,000,000