Description of the Business and Summary of Significant Accounting Policies (Policies )	6 Months Ended
Jun. 30, 2020
Description of the Business and Summary of Significant Accounting Policies
Basis of Presentation	Basis of Presentation The accompanying unaudited consolidated financial statements were prepared in accordance with instructions for Form 10-Q and, therefore, do not include all disclosures necessary for a complete presentation of the consolidated balance sheets, consolidated statements of income, consolidated statements of comprehensive income, consolidated statements of shareholders’ equity and consolidated statements of cash flows in conformity with U.S. generally accepted accounting principles (“GAAP”). However, all normal recurring adjustments which are, in the opinion of management, necessary for the fair presentation of the interim financial statements have been included. The results of operations for the three and six-month periods ended June 30, 2020 are not necessarily indicative of the results which may be expected for the entire year. For further information, refer to the consolidated financial statements and footnotes included in the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 12, 2020.
Principles of Consolidation	Principles of Consolidation These consolidated financial statements include the amounts of the Company, the Bank, with locations in Bloomington, Greenwood, Minneapolis (2), St. Louis Park, Orono, and St. Paul, Minnesota, BWB Holdings, LLC, Bridgewater Investment Management, Inc., and Bridgewater Risk Management, Inc. All significant intercompany balances and transactions have been eliminated in consolidation.
Use of Estimates in Preparation of Financial Statements	Use of Estimates in Preparation of Financial Statements The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. Information available which could affect judgements includes, but is not limited to, changes in interest rates, changes in the performance of the economy, including COVID-19 pandemic related changes, and changes in the financial condition of borrowers. Material estimates that are particularly susceptible to significant change in the near term include the determination of the allowance for loan losses, calculation of deferred tax assets, fair value of financial instruments, and investment securities impairment.
Paycheck Protection Program Loan Segment	Paycheck Protection Program Loan Segment The Company maintains a separate general valuation allowance for each portfolio segment. The Paycheck Protection Program, or PPP, loan segment was added by the Company in the second quarter of 2020. PPP loans are loans to businesses, sole proprietorships, independent contractors and self-employed individuals who meet certain criteria and eligibility requirements through a loan program established by the CARES Act and administered through the Small Business Administration (SBA). PPP loans generally have a two year term and earn interest at 1%. The Company believes that the primary source of repayment will be forgiveness granted by the SBA in accordance with the terms of the program. Credit risk in these loans is limited due to a full guarantee by the U.S. Government. The Company does not assign risk ratings to loans in this segment and will continue to monitor segment performance as circumstances evolve.
Impact of Recent Accounting Standards	Paycheck Protection Program Loan Segment The Company maintains a separate general valuation allowance for each portfolio segment. The Paycheck Protection Program, or PPP, loan segment was added by the Company in the second quarter of 2020. PPP loans are loans to businesses, sole proprietorships, independent contractors and self-employed individuals who meet certain criteria and eligibility requirements through a loan program established by the CARES Act and administered through the Small Business Administration (SBA). PPP loans generally have a two year term and earn interest at 1%. The Company believes that the primary source of repayment will be forgiveness granted by the SBA in accordance with the terms of the program. Credit risk in these loans is limited due to a full guarantee by the U.S. Government. The Company does not assign risk ratings to loans in this segment and will continue to monitor segment performance as circumstances evolve.
Subsequent Events	Subsequent Events Subsequent events have been evaluated through August 6, 2020, which is the date the consolidated financial statements were available to be issued.

The entire disclosure for the basis of accounting, or basis of presentation, used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).

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