Litigation	3 Months Ended
Mar. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Litigation	Litigation In the ordinary course of our business, we are routinely made a defendant in or a party to pending or threatened legal actions or proceedings which, in some cases, seek substantial monetary damages from or other forms of relief against us. In our opinion, after consultation with legal counsel, we believe it unlikely that such actions or proceedings will have a material adverse effect on our financial condition, results of operations or liquidity. New York Community Bancorp, Inc. Merger-related Litigation Following the announcement of the execution of the Agreement and Plan of Merger with New York Community Bancorp, Inc., or NYCB, on October 28, 2015, referred to as the NYCB Merger Agreement, six lawsuits challenging the proposed merger with NYCB, or the NYCB Merger, were filed in the Supreme Court of the State of New York, County of Nassau. These actions were captioned: (1) Sandra E. Weiss IRA v. Chrin, et al., Index No. 607132/2015 (filed November 4, 2015); (2) Raul v. Palleschi, et al., Index No. 607238/2015 (filed November 6, 2015); (3) Lowinger v. Redman, et al., Index No. 607268/2015 (filed November 9, 2015); (4) Minzer v. Astoria Fin. Corp., et al., Index No. 607358/2015 (filed November 12, 2015); (5) MSS 12-09 Trust v. Palleschi, et al., Index No. 607472/2015 (filed November 13, 2015); and (6) The Firemen’s Retirement System of St. Louis v. Keegan, et al., Index No. 607612/2015 (filed November 23, 2015). On January 15, 2016, the court consolidated the New York lawsuits under the caption In re Astoria Financial Corporation Shareholders Litigation, Index No. 607132/2015. Each of the lawsuits was a putative class action filed on behalf of the stockholders of Astoria and named as defendants Astoria, its directors and NYCB, or collectively, the defendants. The NYCB Merger Agreement was terminated effective January 1, 2017. On February 23, 2017, in light of the termination of the NYCB Merger Agreement, the defendants and the plaintiffs agreed to voluntarily discontinue the consolidated lawsuits without prejudice and without any costs to any party. For additional information regarding the NYCB Merger-related litigation, see Part I, Item 3, “Legal Proceedings,” in our 2016 Annual Report on Form 10-K. Sterling Merger-related Litigation Following the announcement of the execution of the Sterling Merger Agreement, a number of lawsuits challenging the proposed Sterling Merger were filed: (1) MSS 1209 Trust v. Astoria Financial Corporation, et al, Index No. 602161/2017, filed March 13, 2017 in the Supreme Court of the State of New York, County of Nassau, or the MSS Complaint; (2) Parshall v. Astoria Financial Corporation, et al, Case No. 2:17-cv-02165, filed April 10, 2017 in the United States District Court for the Eastern District of New York, or the Parshall Complaint; (3) Minzer v. Astoria Financial Corporation, et al., Case No. 2017-0284, filed April 12, 2017 in the Court of Chancery of the State of Delaware, or the Minzer Complaint; (4) O’Connell v. Astoria Financial Corporation, et al., Index No. 603703/2017, filed April 28, 2017 in the Supreme Court of the State of New York, County of Nassau, or the O’Connell Complaint, and together with the MSS Complaint and the Minzer Complaint, the State Court Complaints; and (5) Jenkins v. Astoria Financial Corporation, et al., filed May 2, 2017 in the United States District Court for the Eastern District of New York, or the Jenkins Complaint, and together with the Parshall Complaint, the Federal Complaints. Each of these lawsuits is a putative class action filed on behalf of stockholders of Astoria and names as defendants Astoria, its directors and Sterling. The State Court Complaints generally allege that the directors of Astoria breached their fiduciary duties in connection with their approval of the Sterling Merger Agreement because they failed to properly value Astoria and to take steps to maximize value to Astoria’s public stockholders, resulting in inadequate merger consideration. The State Court Complaints further variously allege that the directors of Astoria approved the Sterling Merger through a flawed sales process, alleging the absence of a competitive sales process and that the process was tainted by certain alleged conflicts of interest on the part of the Astoria directors. The State Court Complaints also allege that the directors of Astoria breached their fiduciary duties because they agreed to unreasonable deal protection devices that allegedly preclude other bidders from making a successful competing offer for Astoria, including, among others, a no solicitation provision that allegedly prevents other buyers from participating in discussions which may lead to a superior proposal, a recurring and unlimited information rights provision, which allegedly gives Astoria 24 hours to provide Sterling unfettered access to confidential, non-public information about competing proposals from third parties, and a provision that requires Astoria to pay Sterling a termination fee of $75.7 million under certain circumstances. The State Court Complaints further allege that Sterling aided and abetted the alleged fiduciary breaches by the Astoria Board of Directors. The Federal Complaints variously allege that the defendants violated federal securities laws by disseminating a registration statement that omits material information with respect to the Sterling Merger, including because it allegedly omits material information regarding Astoria’s and Sterling’s financial projections and financial analyses performed by their respective financial advisors, as well as material information regarding the process leading to the proposed Sterling Merger. The O’Connell Complaint and the Minzer Complaint also allege that the registration statement is materially misleading. Plaintiffs in the state and federal actions seek, among other things, an order enjoining completion of the proposed Sterling Merger, additional disclosure, rescission of the transaction or rescissory damages if the Sterling Merger is consummated, and an award of costs and attorneys’ fees. In addition, on April 26, 2017, a lawsuit challenging the proposed Sterling Merger was filed in the Supreme Court of the State of New York, County of Rockland, Garfield v. Sterling Bancorp, et al, Index No. 031888/2017. This lawsuit is also a putative class action, but was brought on behalf of the stockholders of Sterling and names Sterling, its directors, and Astoria as defendants. The complaint alleges, among other things, that Astoria has aided and abetted a breach of the Sterling directors’ fiduciary duty of candor by jointly filing a materially deficient and misleading proxy statement. The complaint states that plaintiffs are seeking an order, requiring, among other things, the defendants to cause Sterling to make corrective and complete disclosures on the proxy statement, or enjoinment and unwinding of the proposed Sterling Merger Agreement if they do not, and an award of rescissory and other damages to plaintiffs, including attorneys’ fees and costs. The defendants believe these actions are without merit. Accordingly, no liability or reserve has been recognized in our consolidated statement of financial condition at March 31, 2017 with respect to these matters. Other potential plaintiffs may file additional lawsuits challenging the proposed Sterling Merger. The outcome of the pending and any additional future litigation is uncertain. If the cases are not resolved, these lawsuits could result in substantial costs to Astoria, including any costs associated with the indemnification of Astoria’s directors and officers. No assurance can be given at this time that the litigation against us will be resolved in our favor, that this litigation will not be costly to defend, that this litigation will not have an impact on our financial condition or results of operations or that, ultimately, any such impact will not be material.

Litigation

In the ordinary course of our business, we are routinely made a defendant in or a party to pending or threatened legal actions or proceedings which, in some cases, seek substantial monetary damages from or other forms of relief against us. In our opinion, after consultation with legal counsel, we believe it unlikely that such actions or proceedings will have a material adverse effect on our financial condition, results of operations or liquidity.

New York Community Bancorp, Inc. Merger-related Litigation

Following the announcement of the execution of the Agreement and Plan of Merger with New York Community Bancorp, Inc., or NYCB, on October 28, 2015, referred to as the NYCB Merger Agreement, six lawsuits challenging the proposed merger with NYCB, or the NYCB Merger, were filed in the Supreme Court of the State of New York, County of Nassau. These actions were captioned: (1) Sandra E. Weiss IRA v. Chrin, et al., Index No. 607132/2015 (filed November 4, 2015); (2) Raul v. Palleschi, et al., Index No. 607238/2015 (filed November 6, 2015); (3) Lowinger v. Redman, et al., Index No. 607268/2015 (filed November 9, 2015); (4) Minzer v. Astoria Fin. Corp., et al., Index No. 607358/2015 (filed November 12, 2015); (5) MSS 12-09 Trust v. Palleschi, et al., Index No. 607472/2015 (filed November 13, 2015); and (6) The Firemen’s Retirement System of St. Louis v. Keegan, et al., Index No. 607612/2015 (filed November 23, 2015). On January 15, 2016, the court consolidated the New York lawsuits under the caption In re Astoria Financial Corporation Shareholders Litigation, Index No. 607132/2015. Each of the lawsuits was a putative class action filed on behalf of the stockholders of Astoria and named as defendants Astoria, its directors and NYCB, or collectively, the defendants. The NYCB Merger Agreement was terminated effective January 1, 2017.

On February 23, 2017, in light of the termination of the NYCB Merger Agreement, the defendants and the plaintiffs agreed to voluntarily discontinue the consolidated lawsuits without prejudice and without any costs to any party. For additional information regarding the NYCB Merger-related litigation, see Part I, Item 3, “Legal Proceedings,” in our 2016 Annual Report on Form 10-K.

Sterling Merger-related Litigation

Following the announcement of the execution of the Sterling Merger Agreement, a number of lawsuits challenging the proposed Sterling Merger were filed: (1) MSS 1209 Trust v. Astoria Financial Corporation, et al, Index No. 602161/2017, filed March 13, 2017 in the Supreme Court of the State of New York, County of Nassau, or the MSS Complaint; (2) Parshall v. Astoria Financial Corporation, et al, Case No. 2:17-cv-02165, filed April 10, 2017 in the United States District Court for the Eastern District of New York, or the Parshall Complaint; (3) Minzer v. Astoria Financial Corporation, et al., Case No. 2017-0284, filed April 12, 2017 in the Court of Chancery of the State of Delaware, or the Minzer Complaint; (4) O’Connell v. Astoria Financial Corporation, et al., Index No. 603703/2017, filed April 28, 2017 in the Supreme Court of the State of New York, County of Nassau, or the O’Connell Complaint, and together with the MSS Complaint and the Minzer Complaint, the State Court Complaints; and (5) Jenkins v. Astoria Financial Corporation, et al., filed May 2, 2017 in the United States District Court for the Eastern District of New York, or the Jenkins Complaint, and together with the Parshall Complaint, the Federal Complaints. Each of these lawsuits is a putative class action filed on behalf of stockholders of Astoria and names as defendants Astoria, its directors and Sterling.

The State Court Complaints generally allege that the directors of Astoria breached their fiduciary duties in connection with their approval of the Sterling Merger Agreement because they failed to properly value Astoria and to take steps to maximize value to Astoria’s public stockholders, resulting in inadequate merger consideration. The State Court Complaints further variously allege that the directors of Astoria approved the Sterling Merger through a flawed sales process, alleging the absence of a competitive sales process and that the process was tainted by certain alleged conflicts of interest on the part of the Astoria directors. The State Court Complaints also allege that the directors of Astoria breached their fiduciary duties because they agreed to unreasonable deal protection devices that allegedly preclude other bidders from making a successful competing offer for Astoria, including, among others, a no solicitation provision that allegedly prevents other buyers from participating in discussions which may lead to a superior proposal, a recurring and unlimited information rights provision, which allegedly gives Astoria 24 hours to provide Sterling unfettered access to confidential, non-public information about competing proposals from third parties, and a provision that requires Astoria to pay Sterling a termination fee of $75.7 million under certain circumstances. The State Court Complaints further allege that Sterling aided and abetted the alleged fiduciary breaches by the Astoria Board of Directors.

The Federal Complaints variously allege that the defendants violated federal securities laws by disseminating a registration statement that omits material information with respect to the Sterling Merger, including because it allegedly omits material information regarding Astoria’s and Sterling’s financial projections and financial analyses performed by their respective financial advisors, as well as material information regarding the process leading to the proposed Sterling Merger. The O’Connell Complaint and the Minzer Complaint also allege that the registration statement is materially misleading.

Plaintiffs in the state and federal actions seek, among other things, an order enjoining completion of the proposed Sterling Merger, additional disclosure, rescission of the transaction or rescissory damages if the Sterling Merger is consummated, and an award of costs and attorneys’ fees.

In addition, on April 26, 2017, a lawsuit challenging the proposed Sterling Merger was filed in the Supreme Court of the State of New York, County of Rockland, Garfield v. Sterling Bancorp, et al, Index No. 031888/2017. This lawsuit is also a putative class action, but was brought on behalf of the stockholders of Sterling and names Sterling, its directors, and Astoria as defendants. The complaint alleges, among other things, that Astoria has aided and abetted a breach of the Sterling directors’ fiduciary duty of candor by jointly filing a materially deficient and misleading proxy statement. The complaint states that plaintiffs are seeking an order, requiring, among other things, the defendants to cause Sterling to make corrective and complete disclosures on the proxy statement, or enjoinment and unwinding of the proposed Sterling Merger Agreement if they do not, and an award of rescissory and other damages to plaintiffs, including attorneys’ fees and costs.

The defendants believe these actions are without merit. Accordingly, no liability or reserve has been recognized in our consolidated statement of financial condition at March 31, 2017 with respect to these matters.

Other potential plaintiffs may file additional lawsuits challenging the proposed Sterling Merger. The outcome of the pending and any additional future litigation is uncertain. If the cases are not resolved, these lawsuits could result in substantial costs to Astoria, including any costs associated with the indemnification of Astoria’s directors and officers. No assurance can be given at this time that the litigation against us will be resolved in our favor, that this litigation will not be costly to defend, that this litigation will not have an impact on our financial condition or results of operations or that, ultimately, any such impact will not be material.