Mergers and Acquisitions - Summary of Fair Value of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Sep. 01, 2018	Jul. 01, 2017
Brand Group Holdings, Inc.
Business Acquisition [Line Items]
Cash and cash equivalents	$ 193,436
Securities	71,246
Loans, including mortgage loans held for sale	1,589,254
Premises and equipment	20,070
Intangible assets	349,416
Other assets	112,050
Total assets	2,335,472
Deposits	1,714,177
Borrowings	90,912
Other liabilities	55,930
Total liabilities	1,861,019
Metropolitan Bancgroup, Inc.
Business Acquisition [Line Items]
Cash and cash equivalents		$ 47,556
Securities		108,697
Loans, including mortgage loans held for sale		967,804
Premises and equipment		8,576
Other real estate owned		1,203
Intangible assets		147,478
Other assets		69,567
Total assets		1,350,881
Deposits		942,084
Borrowings		174,522
Other liabilities		20,685
Total liabilities		$ 1,137,291
Brand Mortgage Group, LLC
Business Acquisition [Line Items]
Borrowings	34,139
Loans held for sale	$ 48,100

Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Deposits

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Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Loans, Net

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Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Other Real Estate Owned

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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Loans Held for Sale

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of assets acquired at the acquisition date.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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