Business Combinations - Summary of Assets and Liabilities Acquired (Details) - American Enterprise Bankshares Inc. $ in Thousands	Mar. 01, 2016 USD ($)
Assets
Cash and cash equivalents	$ 36,259
Investment securities	4,556
Loans	147,304
Premises and equipment	7,145
Other real estate	809
Core deposit intangible	1,310
Deferred tax asset	5,877
Other assets	365
Fair value of assets acquired	203,625
Liabilities
Noninterest-bearing demand deposits	64,366
Interest-bearing deposits	117,458
Total deposits	181,824
Other liabilities	4,206
Fair value of liabilities assumed	$ 186,030

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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, after allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date, classified as noncurrent.

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The amount of identifiable intangible assets recognized as of 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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