Significant Estimates and Concentrations	12 Months Ended
Dec. 31, 2019
Significant Estimates and Concentrations
Significant Estimates and Concentrations	Note 22: Significant Estimates and Concentrations Accounting principles generally accepted in the United States of America require disclosure of certain significant estimates and current vulnerabilities due to certain concentrations. Estimates related to the provision and allowance for loan losses are reflected in the footnotes regarding loans and the allowance for loan losses (Notes 1 and 4). Estimates related to mortgage servicing rights are reflected in the notes on mortgage servicing rights and loan servicing (Notes 1 and 6). Estimates related to fair values are reflected in the footnote regarding fair values (Note 21). Current vulnerabilities due to certain concentrations of credit risk are discussed in the footnote on commitments, credit risk, and contingencies (Note 23). Other significant estimates and concentrations not discussed in those footnotes include: Mortgage‑backed Securities and Secondary Mortgage Market Programs The Company is involved in government programs for issuing mortgage‑backed securities (MBS). The objective of these programs is to facilitate secondary market activities in order to provide funding for the multi‑family mortgage market. The Company is subject to cancellation of secondary mortgage market programs, rapid increases in general interest rates, and competition associated with conventional mortgage programs. In addition, the Company could be responsible for covering shortfalls in amounts due to investors for delinquencies or foreclosures. No amounts have been reported in the consolidated financial statements since management believes that no near term financial losses will be incurred and these MBS programs will not be significantly affected by the controlling regulatory bodies. Major Customer The Company had no major customers whose business represented more than 10% of revenues during the year ended December 31, 2019 or 2018. For the year ended 2017 the Company had a major customer of the Mortgage Warehousing segment, whose business represented $14.3 million, or 10% of total revenues.

Note 22: Significant Estimates and Concentrations

Accounting principles generally accepted in the United States of America require disclosure of certain significant estimates and current vulnerabilities due to certain concentrations. Estimates related to the provision and allowance for loan losses are reflected in the footnotes regarding loans and the allowance for loan losses (Notes 1 and 4). Estimates related to mortgage servicing rights are reflected in the notes on mortgage servicing rights and loan servicing (Notes 1 and 6). Estimates related to fair values are reflected in the footnote regarding fair values (Note 21). Current vulnerabilities due to certain concentrations of credit risk are discussed in the footnote on commitments, credit risk, and contingencies (Note 23). Other significant estimates and concentrations not discussed in those footnotes include:

Mortgage‑backed Securities and Secondary Mortgage Market Programs

The Company is involved in government programs for issuing mortgage‑backed securities (MBS). The objective of these programs is to facilitate secondary market activities in order to provide funding for the multi‑family mortgage market.

The Company is subject to cancellation of secondary mortgage market programs, rapid increases in general interest rates, and competition associated with conventional mortgage programs. In addition, the Company could be responsible for covering shortfalls in amounts due to investors for delinquencies or foreclosures. No amounts have been reported in the consolidated financial statements since management believes that no near term financial losses will be incurred and these MBS programs will not be significantly affected by the controlling regulatory bodies.

Major Customer

The Company had no major customers whose business represented more than 10% of revenues during the year ended December 31, 2019 or 2018. For the year ended 2017 the Company had a major customer of the Mortgage Warehousing segment, whose business represented $14.3 million, or 10% of total revenues.