Nature of Operations and Summary of Significant Accounting Policies	6 Months Ended
Jun. 30, 2016
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 Northeast 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”), BOC Investment, LLC (“BOC”) and Mitchell Street Apartments Investments, LLC (“Mitchell Street”). 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, 2015. 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 six-month period ended June 30, 2016 are not necessarily indicative of results that may be expected for any other interim period or the entire fiscal year ending December 31, 2016. 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, 2015 except as described further below in this Note 1. Recent Accounting Pronouncements In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606),” with an original effective date for annual reporting periods beginning after December 15, 2016. 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. In August 2015, the FASB issued ASU No. 2015-14, which defers the effective date of ASU 2014-09 to annual and interim reporting periods in fiscal years beginning after December 15, 2017. Earlier application is permitted only as of annual and interim reporting periods in fiscal years beginning after December 15, 2016. In March 2016, the FASB issued ASU No. 2016-08, “Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net.” The ASU intends to improve the operability and understandability of the implementation guidance of ASU 2014-09 on principal versus agent considerations. In April and May 2016, the FASB also issued ASU No. 2016-10 and No. 2016-12 related to Topic 606. The amendments do not change the core principals of the previously issued guidance, but instead further clarify and provide implementation guidance for certain aspects of the original ASU. The Corporation intends to adopt the accounting standards during the first quarter of 2018, as required, and is currently evaluating the impact on its results of operations, financial position, and liquidity. In June 2016, the FASB issued ASU 2016-13, “Financial Instruments- Credit Losses (Topic 326).” The ASU replaces the incurred loss impairment methodology for recognizing credit losses with a methodology that reflects all expected credit losses. The ASU also requires consideration of a broader range of information to inform credit loss estimates, including such factors as past events, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. The amendments affect loans, debt securities, trade receivables, net investments in leases, off-balance-sheet credit exposures, and any other financial asset not excluded from the scope that have the contractual right to receive cash. Entities will apply the amendments in the ASU through a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is effective. The ASU is effective for public companies for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted as of the fiscal years beginning after December 15, 2018. The Corporation intends to adopt the accounting standard during the first quarter of 2020, as required, and is currently evaluating the impact on its results of operations, financial position, and liquidity.

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 Northeast 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”), BOC Investment, LLC (“BOC”) and Mitchell Street Apartments Investments, LLC (“Mitchell Street”). 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, 2015. 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 six-month period ended June 30, 2016 are not necessarily indicative of results that may be expected for any other interim period or the entire fiscal year ending December 31, 2016. 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, 2015 except as described further below in this Note 1.

Recent Accounting Pronouncements

In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606),” with an original effective date for annual reporting periods beginning after December 15, 2016. 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. In August 2015, the FASB issued ASU No. 2015-14, which defers the effective date of ASU 2014-09 to annual and interim reporting periods in fiscal years beginning after December 15, 2017. Earlier application is permitted only as of annual and interim reporting periods in fiscal years beginning after December 15, 2016. In March 2016, the FASB issued ASU No. 2016-08, “Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net.” The ASU intends to improve the operability and understandability of the implementation guidance of ASU 2014-09 on principal versus agent considerations. In April and May 2016, the FASB also issued ASU No. 2016-10 and No. 2016-12 related to Topic 606. The amendments do not change the core principals of the previously issued guidance, but instead further clarify and provide implementation guidance for certain aspects of the original ASU. The Corporation intends to adopt the accounting standards during the first quarter of 2018, as required, and is currently evaluating the impact on its results of operations, financial position, and liquidity.

In June 2016, the FASB issued ASU 2016-13, “Financial Instruments- Credit Losses (Topic 326).” The ASU replaces the incurred loss impairment methodology for recognizing credit losses with a methodology that reflects all expected credit losses. The ASU also requires consideration of a broader range of information to inform credit loss estimates, including such factors as past events, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. The amendments affect loans, debt securities, trade receivables, net investments in leases, off-balance-sheet credit exposures, and any other financial asset not excluded from the scope that have the contractual right to receive cash. Entities will apply the amendments in the ASU through a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is effective. The ASU is effective for public companies for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted as of the fiscal years beginning after December 15, 2018. The Corporation intends to adopt the accounting standard during the first quarter of 2020, as required, and is currently evaluating the impact on its results of operations, financial position, and liquidity.