Nature of Operations and Summary of Significant Accounting Policies	3 Months Ended
Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations and Summary of Significant Accounting Policies	Nature of Operations and Summary of Significant Accounting Policies Nature of Operations. The accounting and reporting practices of First Business Financial Services, Inc. (the “Corporation”), its wholly-owned subsidiaries, First Business Bank (“FBB”), First Business Bank – Milwaukee (“FBB – Milwaukee”) and Alterra Bank (“Alterra”) have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). FBB, FBB – Milwaukee and Alterra are sometimes referred to together as the “Banks.” FBB operates as a commercial banking institution in the Madison, Wisconsin market, consisting primarily of Dane County and the surrounding areas, with loan production offices in Oshkosh, Appleton, and Green Bay, Wisconsin. FBB also offers trust and investment services through First Business Trust & Investments (“FBTI”), a division of FBB. FBB – Milwaukee operates as a commercial banking institution in the Milwaukee, Wisconsin market, consisting primarily of Waukesha County and the surrounding areas, with a loan production office in Kenosha, Wisconsin. Alterra operates as a commercial banking institution in the Kansas City market and the surrounding areas. The Banks provide a full range of financial services to businesses, business owners, executives, professionals and high net worth individuals. The Banks are subject to competition from other financial institutions and service providers and are also subject to state and federal regulations. FBB has the following wholly-owned subsidiaries: First Business Capital Corp. (“FBCC”), First Madison Investment Corp. (“FMIC”), First Business Equipment Finance, LLC (“FBEF”), Rimrock Road Investment Fund, LLC (“Rimrock Road”) and BOC Investment, LLC (“BOC”). FMIC is located in and was formed under the laws of the state of Nevada. FBB-Milwaukee has one subsidiary, FBB – Milwaukee Real Estate, LLC (“FBBMRE”). Basis of Presentation. The accompanying unaudited Consolidated Financial Statements were prepared in accordance with GAAP and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the Corporation’s Consolidated Financial Statements and footnotes thereto included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2014. The unaudited Consolidated Financial Statements include the accounts of the Corporation and its wholly-owned subsidiaries. In accordance with the provisions of Accounting Standards Codification (“ASC”) Topic 810, the Corporation’s ownership interest in FBFS Statutory Trust II (“Trust II”) has not been consolidated into the financial statements. All significant intercompany balances and transactions have been eliminated in consolidation. Management of the Corporation is required to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements as well as reported amounts of revenues and expenses during the reporting period. Actual results could differ significantly from those estimates. Material estimates that could significantly change in the near-term include the value of foreclosed property, lease residuals, property under operating leases, securities, income taxes and the level of the allowance for loan and lease losses. The results of operations for the three-month period ended March 31, 2015 are not necessarily indicative of results that may be expected for any other interim period or the entire fiscal year ending December 31, 2015. Certain amounts in prior periods may have been reclassified to conform to the current presentation. Subsequent events have been evaluated through the date of the issuance of the Consolidated Financial Statements. No significant subsequent events have occurred through this date requiring adjustment to the financial statements or disclosures. The Corporation has not changed its significant accounting and reporting policies from those disclosed in the Corporation’s Form 10-K for the year ended December 31, 2014 except as described further below in this Note 1. Recent Accounting Pronouncements. In January 2014, the FASB issued ASU No. 2014-01, “ Investments - Equity Method Joint Ventures (Topic 323): Accounting for Investments in Qualified Affordable Housing Projects.” This ASU allows investors in Low Income Housing Tax Credit (LIHTC) programs that meet specified conditions to present the net tax benefits (net of the amortization of the cost of the investment) within income tax expense. The cost of the investments that meet the specified conditions will be amortized in proportion to (and over the same period as) the total expected tax benefits, including the tax credits and other tax benefits, as they are realized on the tax return. The ASU is effective for interim and annual periods beginning after December 15, 2014. The ASU is required to be applied retrospectively, if investors elect the proportional amortization method. However, if investors have existing LIHTC investments accounted for under the effective-yield method at adoption, they may continue to apply that method for those existing investments. The Corporation adopted the accounting standard in the first quarter of 2015 with no impact on its financial position or results of operations. In January 2014, the FASB issued ASU No. 2014-04, “Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure (a consensus of the FASB Emerging Issues Task Force).” This ASU clarifies that an “in substance repossession or foreclosure” occurs, and a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either (1) the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or (2) the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or through a similar agreement. In addition, the amendments require interim and annual disclosure of both the amount of foreclosed residential real estate property held by the creditor and the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure in accordance with local requirements of the applicable jurisdiction. This amendment is effective for fiscal years, and interim periods within those years, beginning after December 15, 2014. An entity can elect to adopt the amendments using either a modified retrospective method or a prospective transition method. Early adoption is permitted. The Corporation adopted the accounting standard in the first quarter of 2015 with no impact on its financial position or results of operations. In August 2014, the FASB issued ASU 2014-14, “Receivables - Troubled Debt Restructuring by Creditors (Subtopic 310-40): Classification of Certain Government-Guaranteed Mortgage Loans upon Foreclosure.” This ASU will require creditors to derecognize certain foreclosed government-guaranteed mortgage loans and to recognize a separate other receivable that is measured at the amount the creditor expects to recover from the guarantor, and to treat the guarantee and the receivable as a single unit of account. The ASU is effective for interim and annual periods beginning after December 15, 2014. An entity can elect a prospective or a modified retrospective transition method, but must use the same transition method that it elected under FASB ASU No. 2014-04, Early adoption is permitted. The Corporation adopted the accounting standard in the first quarter of 2015 with no impact on its financial position or results of operations. In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 666).” The ASU is a converged standard between the FASB and the IASB that provides a single comprehensive revenue recognition model for all contracts with customers across transactions and industries. The primary objective of the ASU is revenue recognition that represents the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU is effective for interim and annual reporting periods beginning after December 15, 2016. The Corporation is in the process of evaluating the impact of this standard but does not expect this standard to have a material impact on the Corporation’s consolidated financial position or results of operations. In June 2014, the FASB issued ASU No. 2014-12, “Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period.” This ASU requires a reporting entity to treat a performance target that affects vesting and that could be achieved after the requisite service period as a performance condition. A reporting entity should apply FASB ASC Topic 718, Compensation-Stock Compensation, to awards with performance conditions that affect vesting. For all entities, ASU 2014-12 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted. ASU 2014-12 may be adopted either prospectively for share-based payment awards granted or modified on or after the effective date, or retrospectively, using a modified retrospective approach. The modified retrospective approach would apply to share-based payment awards outstanding as of the beginning of the earliest annual period presented in the financial statements on adoption, and to all new or modified awards thereafter. While the Corporation does not have any performance-based awards outstanding as of the reporting date, the Corporation’s equity incentive plan does allow for such awards. The Corporation is in the process of evaluating the impact of this standard but does not expect this standard to have a material impact on the Corporation’s consolidated financial position or results of operations. In August 2014, the FASB issued ASU 2014-15, “Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern.” This ASU describes how an entity should assess its ability to meet obligations and sets rules for how this information should be disclosed in the financial statements. The standard provides accounting guidance that will be used along with existing auditing standards. The ASU is effective for interim and annual periods beginning after December 15, 2016. Early application is permitted. The Corporation is in the process of evaluating the impact of this standard but does not expect this standard to have a material impact on the Corporation’s consolidated financial position or results of operations. In February 2015, the FASB issued ASU 2015-02, “Consolidation (Topic 810): Amendments to the Consolidation Analysis.” This ASU changes the way reporting enterprises evaluate whether (a) they should consolidate limited partnerships and similar entities, (b) fees paid to a decision maker or service provider are variable interests in a variable interest entity (VIE), and (c) variable interests in a VIE held by related parties of the reporting enterprise require the reporting enterprise to consolidate the VIE. It also eliminates the VIE consolidation model based on majority exposure to variability that applied to certain investment companies and similar entities. The new guidance excludes money market funds that are required to comply with Rule 2a-7 of the Investment Company Act of 1940 and similar entities from the U.S. GAAP consolidation requirements. The new consolidation guidance is effective for public business entities for annual and interim periods in fiscal years beginning after December 15, 2015. At the effective date, all previous consolidation analysis that the guidance affects must be reconsidered. This includes the consolidation analysis for all VIEs and for all limited partnerships and similar entities that previously were consolidated by the general partner even though the entities were not VIEs. Early adoption is permitted, including early adoption in an interim period. If a reporting enterprise chooses to early adopt in an interim period, adjustments resulting from the revised consolidation analysis must be reflected as of the beginning of the fiscal year that includes that interim period. The Corporation is in the process of evaluating the impact of this standard but does not expect this standard to have a material impact on the Corporation’s consolidated financial position or results of operations.

Nature of Operations and Summary of Significant Accounting Policies

Nature of Operations. The accounting and reporting practices of First Business Financial Services, Inc. (the “Corporation”), its wholly-owned subsidiaries, First Business Bank (“FBB”), First Business Bank – Milwaukee (“FBB – Milwaukee”) and Alterra Bank (“Alterra”) have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). FBB, FBB – Milwaukee and Alterra are sometimes referred to together as the “Banks.” FBB operates as a commercial banking institution in the Madison, Wisconsin market, consisting primarily of Dane County and the surrounding areas, with loan production offices in Oshkosh, Appleton, and Green Bay, Wisconsin. FBB also offers trust and investment services through First Business Trust & Investments (“FBTI”), a division of FBB. FBB – Milwaukee operates as a commercial banking institution in the Milwaukee, Wisconsin market, consisting primarily of Waukesha County and the surrounding areas, with a loan production office in Kenosha, Wisconsin. Alterra operates as a commercial banking institution in the Kansas City market and the surrounding areas. The Banks provide a full range of financial services to businesses, business owners, executives, professionals and high net worth individuals. The Banks are subject to competition from other financial institutions and service providers and are also subject to state and federal regulations. FBB has the following wholly-owned subsidiaries: First Business Capital Corp. (“FBCC”), First Madison Investment Corp. (“FMIC”), First Business Equipment Finance, LLC (“FBEF”), Rimrock Road Investment Fund, LLC (“Rimrock Road”) and BOC Investment, LLC (“BOC”). FMIC is located in and was formed under the laws of the state of Nevada. FBB-Milwaukee has one subsidiary, FBB – Milwaukee Real Estate, LLC (“FBBMRE”).

Basis of Presentation. The accompanying unaudited Consolidated Financial Statements were prepared in accordance with GAAP and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the Corporation’s Consolidated Financial Statements and footnotes thereto included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2014. The unaudited Consolidated Financial Statements include the accounts of the Corporation and its wholly-owned subsidiaries. In accordance with the provisions of Accounting Standards Codification (“ASC”) Topic 810, the Corporation’s ownership interest in FBFS Statutory Trust II (“Trust II”) has not been consolidated into the financial statements. All significant intercompany balances and transactions have been eliminated in consolidation.

Management of the Corporation is required to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements as well as reported amounts of revenues and expenses during the reporting period. Actual results could differ significantly from those estimates. Material estimates that could significantly change in the near-term include the value of foreclosed property, lease residuals, property under operating leases, securities, income taxes and the level of the allowance for loan and lease losses. The results of operations for the three-month period ended March 31, 2015 are not necessarily indicative of results that may be expected for any other interim period or the entire fiscal year ending December 31, 2015. Certain amounts in prior periods may have been reclassified to conform to the current presentation. Subsequent events have been evaluated through the date of the issuance of the Consolidated Financial Statements. No significant subsequent events have occurred through this date requiring adjustment to the financial statements or disclosures.

The Corporation has not changed its significant accounting and reporting policies from those disclosed in the Corporation’s Form 10-K for the year ended December 31, 2014 except as described further below in this Note 1.

Recent Accounting Pronouncements.

In January 2014, the FASB issued ASU No. 2014-01, “ Investments - Equity Method Joint Ventures (Topic 323): Accounting for Investments in Qualified Affordable Housing Projects.” This ASU allows investors in Low Income Housing Tax Credit (LIHTC) programs that meet specified conditions to present the net tax benefits (net of the amortization of the cost of the investment) within income tax expense. The cost of the investments that meet the specified conditions will be amortized in proportion to (and over the same period as) the total expected tax benefits, including the tax credits and other tax benefits, as they are realized on the tax return. The ASU is effective for interim and annual periods beginning after December 15, 2014. The ASU is required to be applied retrospectively, if investors elect the proportional amortization method. However, if investors have existing LIHTC investments accounted for under the effective-yield method at adoption, they may continue to apply that method for those existing investments. The Corporation adopted the accounting standard in the first quarter of 2015 with no impact on its financial position or results of operations.

In January 2014, the FASB issued ASU No. 2014-04, “Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure (a consensus of the FASB Emerging Issues Task Force).” This ASU clarifies that an “in substance repossession or foreclosure” occurs, and a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either (1) the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or (2) the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or through a similar agreement. In addition, the amendments require interim and annual disclosure of both the amount of foreclosed residential real estate property held by the creditor and the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure in accordance with local requirements of the applicable jurisdiction. This amendment is effective for fiscal years, and interim periods within those years, beginning after December 15, 2014. An entity can elect to adopt the amendments using either a modified retrospective method or a prospective transition method. Early adoption is permitted. The Corporation adopted the accounting standard in the first quarter of 2015 with no impact on its financial position or results of operations.

In August 2014, the FASB issued ASU 2014-14, “Receivables - Troubled Debt Restructuring by Creditors (Subtopic 310-40): Classification of Certain Government-Guaranteed Mortgage Loans upon Foreclosure.” This ASU will require creditors to derecognize certain foreclosed government-guaranteed mortgage loans and to recognize a separate other receivable that is measured at the amount the creditor expects to recover from the guarantor, and to treat the guarantee and the receivable as a single unit of account. The ASU is effective for interim and annual periods beginning after December 15, 2014. An entity can elect a prospective or a modified retrospective transition method, but must use the same transition method that it elected under FASB ASU No. 2014-04, Early adoption is permitted. The Corporation adopted the accounting standard in the first quarter of 2015 with no impact on its financial position or results of operations.

In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 666).” The ASU is a converged standard between the FASB and the IASB that provides a single comprehensive revenue recognition model for all contracts with customers across transactions and industries. The primary objective of the ASU is revenue recognition that represents the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU is effective for interim and annual reporting periods beginning after December 15, 2016. The Corporation is in the process of evaluating the impact of this standard but does not expect this standard to have a material impact on the Corporation’s consolidated financial position or results of operations.

In June 2014, the FASB issued ASU No. 2014-12, “Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period.” This ASU requires a reporting entity to treat a performance target that affects vesting and that could be achieved after the requisite service period as a performance condition. A reporting entity should apply FASB ASC Topic 718, Compensation-Stock Compensation, to awards with performance conditions that affect vesting. For all entities, ASU 2014-12 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted. ASU 2014-12 may be adopted either prospectively for share-based payment awards granted or modified on or after the effective date, or retrospectively, using a modified retrospective approach. The modified retrospective approach would apply to share-based payment awards outstanding as of the beginning of the earliest annual period presented in the financial statements on adoption, and to all new or modified awards thereafter. While the Corporation does not have any performance-based awards outstanding as of the reporting date, the Corporation’s equity incentive plan does allow for such awards. The Corporation is in the process of evaluating the impact of this standard but does not expect this standard to have a material impact on the Corporation’s consolidated financial position or results of operations.

In August 2014, the FASB issued ASU 2014-15, “Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern.” This ASU describes how an entity should assess its ability to meet obligations and sets rules for how this information should be disclosed in the financial statements. The standard provides accounting guidance that will be used along with existing auditing standards. The ASU is effective for interim and annual periods beginning after December 15, 2016. Early application is permitted. The Corporation is in the process of evaluating the impact of this standard but does not expect this standard to have a material impact on the Corporation’s consolidated financial position or results of operations.

In February 2015, the FASB issued ASU 2015-02, “Consolidation (Topic 810): Amendments to the Consolidation Analysis.” This ASU changes the way reporting enterprises evaluate whether (a) they should consolidate limited partnerships and similar entities, (b) fees paid to a decision maker or service provider are variable interests in a variable interest entity (VIE), and (c) variable interests in a VIE held by related parties of the reporting enterprise require the reporting enterprise to consolidate the VIE. It also eliminates the VIE consolidation model based on majority exposure to variability that applied to certain investment companies and similar entities. The new guidance excludes money market funds that are required to comply with Rule 2a-7 of the Investment Company Act of 1940 and similar entities from the U.S. GAAP consolidation requirements. The new consolidation guidance is effective for public business entities for annual and interim periods in fiscal years beginning after December 15, 2015. At the effective date, all previous consolidation analysis that the guidance affects must be reconsidered. This includes the consolidation analysis for all VIEs and for all limited partnerships and similar entities that previously were consolidated by the general partner even though the entities were not VIEs. Early adoption is permitted, including early adoption in an interim period. If a reporting enterprise chooses to early adopt in an interim period, adjustments resulting from the revised consolidation analysis must be reflected as of the beginning of the fiscal year that includes that interim period. The Corporation is in the process of evaluating the impact of this standard but does not expect this standard to have a material impact on the Corporation’s consolidated financial position or results of operations.