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Acquisition Activity (Details) $ / shares in Units, $ in Millions		9 Months Ended
	May 30, 2021 USD ($)	Sep. 30, 2021 USD ($) $ / shares
Business Acquisition [Line Items]
Share price (in dollars per share) | $ / shares		$ 16.95
Merger transaction costs		$ 7.9
First Midwest
Business Acquisition [Line Items]
Shares exchange ratio	1.1336
Transaction value	$ 2,210.0
First Midwest | Former First Midwest Stockholders
Business Acquisition [Line Items]
Percentage of voting interests acquired	44.00%
First Midwest | Series A Preferred Stock
Business Acquisition [Line Items]
Dividend rate	7.00%
First Midwest | Series C Preferred Stock
Business Acquisition [Line Items]
Dividend rate	7.00%

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Business Acquisition, Equity Interest Issued Or Issuable, Exchange Ratio

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The percentage rate used to calculate dividend payments on preferred stock.

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