Organization and Going Concern	12 Months Ended
Dec. 31, 2016
Organization and Going Concern [Abstract]
Organization and Going Concern	Note 1 – Organization and Going Concern AmBase Corporation ("AmBase" or the "Company") is a holding company which has an equity investment in a real estate development property to develop real property in New York, New York and owns a commercial office building in Greenwich, Connecticut that is managed and operated by the Company. The Company's assets currently consist primarily of cash and cash equivalents, an equity investment in a real estate development property and real estate owned. As further discussed in Note 4, the Company owns an equity interest in a real estate development property through a joint venture agreement to purchase and develop real property located at 105 through 111 West 57^th Street in New York, New York (the "111 West 57^th Property"). The Company is engaged in the management of its assets and liabilities. A fundamental principle of the preparation of financial statements in accordance with GAAP is the assumption that an entity will continue in existence as a going concern, which contemplates continuity of operations and the realization of assets and settlement of liabilities occurring in the ordinary course of business. In accordance with this requirement, the Company has prepared its accompanying consolidated financial statements assuming the Company will continue as a going concern. In 2016, the Company adopted Accounting Standards Update ("ASU") 2014-15 Presentation of Financial Statements—Going Concern (Subtopic 205-40). The Company has incurred operating losses and used cash for operating activities for the past several years. The Company has also made significant investments in the 111 West 57th Street Property since 2013. The Company has continued to keep operating expenses at a reduced level; however, there can be no assurance that the Company's current level of operating expenses will not increase or that other uses of cash will not be necessary. The Company believes that based on its current level of operating expenses, its currently available cash resources together with the line of credit from Mr. Bianco as noted below, may not be sufficient to cover operating cash needs through the twelve month period from the financial statement reporting date. Based on the above factors, management determined there is substantial doubt about the Company's ability to continue as a going concern within one year after the date that the financial statements are issued. The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern. The financial statements do not include adjustments to the carrying value of assets and liabilities which might be necessary should the Company not continue in operation. Over the next several months, the Company will seek to manage its current level of cash and cash equivalents, through various ways, including but not limited to, reducing operating expenses, possible asset sales and/or long term borrowings, although this cannot be assured. In order to continue on a long-term basis, the Company must raise additional capital through the sale of assets or long term borrowings. There can be no assurance that the Company will be able to attain such financing at terms acceptable to the Company, if at all. In May 2016, the Company and Mr. Richard A. Bianco, the Company's Chairman President and Chief Executive Officer ("R. A. Bianco") entered into an agreement for Mr. R. A. Bianco to provide to the Company, a secured working capital line of credit of up to one million dollars ($1,000,000) or additional amount(s) as may be necessary and agreed to on an as needed basis, if and when necessary, subject to customary and market terms and conditions to be agreed upon at such time. A copy of such agreement is filed as exhibit 10.1 to the Company's Form 10-Q for the quarterly period ended March 31, 2016. Pursuant to this agreement in January 2017, Mr. Bianco made a $500,000 loan to the Company for use as working capital. The loan accrues interest at 5.25% per annum and is due on the earlier of the date the Company receives funds from any source sufficient to pay all amounts due under the loan, including accrued interest thereon, or December 31, 2019.

Note 1 – Organization and Going Concern

AmBase Corporation ("AmBase" or the "Company") is a holding company which has an equity investment in a real estate development property to develop real property in New York, New York and owns a commercial office building in Greenwich, Connecticut that is managed and operated by the Company.

The Company's assets currently consist primarily of cash and cash equivalents, an equity investment in a real estate development property and real estate owned. As further discussed in Note 4, the Company owns an equity interest in a real estate development property through a joint venture agreement to purchase and develop real property located at 105 through 111 West 57^th Street in New York, New York (the "111 West 57^th Property"). The Company is engaged in the management of its assets and liabilities.

A fundamental principle of the preparation of financial statements in accordance with GAAP is the assumption that an entity will continue in existence as a going concern, which contemplates continuity of operations and the realization of assets and settlement of liabilities occurring in the ordinary course of business. In accordance with this requirement, the Company has prepared its accompanying consolidated financial statements assuming the Company will continue as a going concern.

In 2016, the Company adopted Accounting Standards Update ("ASU") 2014-15 Presentation of Financial Statements—Going Concern (Subtopic 205-40).

The Company has incurred operating losses and used cash for operating activities for the past several years. The Company has also made significant investments in the 111 West 57th Street Property since 2013. The Company has continued to keep operating expenses at a reduced level; however, there can be no assurance that the Company's current level of operating expenses will not increase or that other uses of cash will not be necessary. The Company believes that based on its current level of operating expenses, its currently available cash resources together with the line of credit from Mr. Bianco as noted below, may not be sufficient to cover operating cash needs through the twelve month period from the financial statement reporting date. Based on the above factors, management determined there is substantial doubt about the Company's ability to continue as a going concern within one year after the date that the financial statements are issued. The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern. The financial statements do not include adjustments to the carrying value of assets and liabilities which might be necessary should the Company not continue in operation.

Over the next several months, the Company will seek to manage its current level of cash and cash equivalents, through various ways, including but not limited to, reducing operating expenses, possible asset sales and/or long term borrowings, although this cannot be assured. In order to continue on a long-term basis, the Company must raise additional capital through the sale of assets or long term borrowings. There can be no assurance that the Company will be able to attain such financing at terms acceptable to the Company, if at all.

In May 2016, the Company and Mr. Richard A. Bianco, the Company's Chairman President and Chief Executive Officer ("R. A. Bianco") entered into an agreement for Mr. R. A. Bianco to provide to the Company, a secured working capital line of credit of up to one million dollars ($1,000,000) or additional amount(s) as may be necessary and agreed to on an as needed basis, if and when necessary, subject to customary and market terms and conditions to be agreed upon at such time. A copy of such agreement is filed as exhibit 10.1 to the Company's Form 10-Q for the quarterly period ended March 31, 2016. Pursuant to this agreement in January 2017, Mr. Bianco made a $500,000 loan to the Company for use as working capital. The loan accrues interest at 5.25% per annum and is due on the earlier of the date the Company receives funds from any source sufficient to pay all amounts due under the loan, including accrued interest thereon, or December 31, 2019.