Summary of Significant Accounting Policies	6 Months Ended
Summary of Significant Accounting Policies	Aug. 29, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of presentation The consolidated financial statements of Apogee Enterprises, Inc. (we, us, our or the Company) have been prepared in accordance with accounting principles generally accepted in the United States. The information included in this Form 10-Q should be read in conjunction with the Company’s Form 10-K for the year ended February 29, 2020. We use the same accounting policies in preparing quarterly and annual financial statements. All adjustments necessary for a fair presentation of quarterly and year to date operating results are reflected herein and are of a normal, recurring nature. The results of operations for the three- and six-month periods ended August 29, 2020 are not necessarily indicative of the results to be expected for the full year. COVID-19 considerations The ongoing COVID-19 pandemic continues to cause volatility and uncertainty in global markets impacting worldwide economic activity. We have experienced some delays in commercial construction projects and orders as a result of COVID-19. In our Architectural Glass and Architectural Framing segments, orders have been delayed or have slowed, as customers and end markets face some uncertainty and delays in timing of work. In our Architectural Services segment, some construction site closures or project delays have occurred, and job sites have had to adjust to increased physical distancing and health-related precautions. Within our Large-Scale Optical (LSO) segment, many customers reopened and the segment's two manufacturing locations resumed normal operations during the second quarter, after being shutdown for most of the first and second quarters, in response to governmental “stay at home” directives. We have also been impacted by quarantine-related absenteeism among our workforce, resulting in labor and capacity constraints at some of our facilities. The extent to which COVID-19 will continue to impact our business will depend on future developments and public health advancements, which are highly uncertain and cannot be predicted with confidence. However, by the end of the second quarter, we have continued to see signs of improvement, including the reopening of retailers, moderating project delays and fewer workforce absences. Furthermore, in response to COVID-19, we have implemented a variety of countermeasures to promote the health and safety of our employees during this pandemic, including health screening, physical distancing practices, enhanced cleaning, use of personal protective equipment, business travel restrictions, and remote work capabilities, in addition to quarantine-related paid leave and other employee assistance programs. Adoption of new accounting standards At the beginning of fiscal 2021, we adopted the guidance in ASU 2016-13, Measurement of Credit Losses on Financial Instruments. The guidance provides for a new impairment model on financial instruments which is based on expected credit losses, which was applied following a modified retrospective approach. Additionally, the new guidance makes targeted improvements to the impairment model for certain available-for-sale debt securities, including eliminating the concept of "other than temporary" from that model. The portion of the guidance related to available-for-sale debt securities was adopted following a prospective approach. The adoption of this ASU did not have a significant impact on earnings or financial condition. Refer to additional disclosures in Notes 2 and 4. Subsequent events We have evaluated subsequent events for potential recognition and disclosure through the date of this filing. Subsequent to the end of the quarter, in September 2020, we sold our McCook, IL building within our LSO segment for $25.1 million. The carrying value of the building was $4.3 million, and we recognized a gain on this sale of approximately $14.8 million, net of taxes and associated transaction costs. We also entered into a separate lease agreement for this facility, which was determined to be an operating lease, and we will have approximately $8.2 million of additional future lease commitments upon commencement of this lease in September 2020. Additionally, in September 2020, we announced the retirement of our Chief Executive Officer, effective February 27, 2021, the end of our current fiscal year, and entered into a transition agreement with him.