Subsequent Events	9 Months Ended
Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Completion of Merger On June 29, 2017, we entered into the Merger Agreement with D.R. Horton and Force Merger Sub, Inc. (“Merger Sub”), a wholly owned subsidiary of D.R. Horton. At the effective time on October 5, 2017, we merged with Merger Sub and we continued as the surviving entity in the Merger. In the Merger, each existing share of our common stock issued and outstanding immediately prior to the effective time (the “Former Forestar Common Stock”) (except for shares of our common stock that were held by us as treasury shares or by us or D.R. Horton or our or their respective subsidiaries) were converted into the right to receive, at the election of the holders of such shares of Former Forestar Common Stock, either an amount in cash equal to the Cash Consideration ($17.75 per share) or one new share of our common stock (the “New Forestar Common Stock”), subject to proration procedures applicable to oversubscription and undersubscription for the Cash Consideration described in the Merger Agreement. The aggregate amount of Cash Consideration paid by D.R. Horton to holders of Former Forestar Common Stock in the Merger was $558,256,000. In the Merger, 10,487,873 shares of New Forestar Common Stock (representing 25% of the outstanding shares of New Forestar Common Stock immediately after the effective time) were issued to the holders of our common stock and 31,451,063 shares of New Forestar Common Stock (representing 75% of the outstanding share of the New Forestar Common Stock immediately after the effective time) were issued to D.R. Horton. Subject to the terms of the Merger Agreement, at the effective time, each equity award made or otherwise denominated in shares of Former Forestar Common Stock that was outstanding immediately prior to the effective time under our equity compensation plans was cancelled and of no further force or effect as of the effective time. In exchange for the cancellation of the equity awards, each holder of such an equity award received from us the Cash Consideration for each share of Former Forestar Common Stock underlying such equity award (and in the case of equity awards that were stock options or stock appreciation rights, less the applicable exercise or strike price, but not less than $0), whether or not otherwise vested as of the effective time. With respect to any of our market-leveraged stock units, the number of shares of Former Forestar Common Stock subject to such equity awards were determined pursuant to the terms set forth in the applicable award agreements and based on a per share value equal to $17.75. We paid our financial advisor a transaction fee of $5,595,000 which was expensed upon closing of the Merger. New Forestar Common Stock continues to be listed and traded on the New York Stock Exchange under the ticker symbol, “FOR.” As of October 5, 2017, we are a majority-owned subsidiary of D.R. Horton, the largest homebuilder by volume in the United States for fifteen consecutive years. We are evaluating the impact of any potential changes in our accounting policies and related party transactions with D.R. Horton post merger and will update our disclosures accordingly in future periods. The merger will be accounted for under the acquisition method in accordance with U.S. GAAP. D.R. Horton is the acquirer for accounting purposes and our consolidated financial statements will continue to be stated at historical cost. Letter of Credit Facility On October 5, 2017, we entered into a Letter of Credit Facility Agreement (the “LC Facility Agreement”) providing for a $30,000,000 secured standby letter of credit facility (the “LC Facility”) with Keybank National Association and other lenders party thereto, as banks, Keybank National Association, as letter of credit issuer and administrative agent, and Keybanc Capital Markets, as sole arranger and sole bookrunner. The LC Facility is secured by $30,000,000 in cash deposited with the administrative agent. We are required to pay a letter of credit fee of 1.25% per annum on the outstanding face amount of the letters of credit issued under the LC Facility, as well as other customary fees and expenses. We also are required to pay an unused facility fee of 0.15% per annum, in each case on the daily amount by which the aggregate commitments exceed the sum of the outstanding letters of credit during each fiscal quarter or portion thereof. The LC Facility Agreement includes customary representations and warranties, affirmative and negative covenants and other undertakings. The LC Facility Agreement also contains customary events of default. If an event of default occurs, all or a portion of the commitments under the LC Facility may be terminated and/or other rights held by the banks under any of the related facility documents (including against the collateral) may be exercised, subject to certain limitations. Termination of Senior Credit Facility On October 5, 2017, in connection with entry into the LC Facility, we terminated our existing senior credit facility (the “Prior Credit Facility”). The Prior Credit Facility provided for a $50,000,000 revolving line of credit that was scheduled to mature on May 15, 2018. This Prior Credit Facility could be prepaid at any time without penalty and included a $50,000,000 sublimit for letters of credit, of which $14,267,000 were outstanding at the time of termination and were transferred to the new LC Facility. 3.75% Convertible Senior Notes On October 5, 2017, in connection with the consummation of the Merger, we entered into a Third Supplemental Indenture (together with the base indenture and the prior supplemental indentures, the "Indenture") to the Indenture relating to our 3.75% Convertible Senior Notes due 2020 (the “Convertible Notes”). Pursuant to the Third Supplemental Indenture, the Convertible Notes are no longer convertible into shares of Former Forestar Common Stock and instead are convertible into cash and shares of New Forestar Common Stock based on the per-share weighted average of the cash and shares of New Forestar Common Stock received by our stockholders that affirmatively made an election in connection with the Merger. As a result of such elections, for each share of Former Forestar Common Stock a holder of Convertible Notes was previously entitled to receive upon conversion of Convertible Notes, such holder is instead entitled to receive $14.19785 in cash and 0.20012 of a share of New Forestar Common Stock. The completion of the Merger constituted a Fundamental Change, as defined in the Indenture. On October 12, 2017, in accordance with the Indenture, we gave notice of the Fundamental Change to holders of the Convertible Notes and made an offer to purchase (a “Fundamental Change Offer”) all or any part (equal to $1,000 or an integral multiple of $1,000) of every holder’s Convertible Notes pursuant to the Fundamental Change Offer on the terms set forth in the Indenture. In the Fundamental Change Offer, we offered to repurchase the Convertible Notes for a price in cash equal to 100% of the aggregate principal amount of Convertible Notes, plus accrued and unpaid interest, if any, to the date of repurchase. Expiration of Tax Benefits Preservation Plan On October 5, 2017 immediately prior to the effective time of the merger, our Tax Benefit Preservation Plan expired pursuant to its terms and all Rights previously distributed to the holders of our common stock pursuant to the Plan expired. 8.50% Senior Secured Notes On October 30, 2017 (the “Redemption Date”), we redeemed the remaining $5,315,000 aggregate principal amount of outstanding 8.50% Senior Secured Notes due 2022 (the “Notes”). Pursuant to the indenture governing the Notes, the Notes were redeemed for $5,928,063, which was the sum of (a) the present value of 104.250% of the outstanding principal amount of the Notes and the scheduled payments of interest thereon through June 1, 2018 discounted as set forth in such indenture to the Redemption Date, plus (b) accrued and unpaid interest to but not including the Redemption Date.

Subsequent Events

Completion of Merger

On June 29, 2017, we entered into the Merger Agreement with D.R. Horton and Force Merger Sub, Inc. (“Merger Sub”), a wholly owned subsidiary of D.R. Horton. At the effective time on October 5, 2017, we merged with Merger Sub and we continued as the surviving entity in the Merger. In the Merger, each existing share of our common stock issued and outstanding immediately prior to the effective time (the “Former Forestar Common Stock”) (except for shares of our common stock that were held by us as treasury shares or by us or D.R. Horton or our or their respective subsidiaries) were converted into the right to receive, at the election of the holders of such shares of Former Forestar Common Stock, either an amount in cash equal to the Cash Consideration ($17.75 per share) or one new share of our common stock (the “New Forestar Common Stock”), subject to proration procedures applicable to oversubscription and undersubscription for the Cash Consideration described in the Merger Agreement. The aggregate amount of Cash Consideration paid by D.R. Horton to holders of Former Forestar Common Stock in the Merger was $558,256,000. In the Merger, 10,487,873 shares of New Forestar Common Stock (representing 25% of the outstanding shares of New Forestar Common Stock immediately after the effective time) were issued to the holders of our common stock and 31,451,063 shares of New Forestar Common Stock (representing 75% of the outstanding share of the New Forestar Common Stock immediately after the effective time) were issued to D.R. Horton.

Subject to the terms of the Merger Agreement, at the effective time, each equity award made or otherwise denominated in shares of Former Forestar Common Stock that was outstanding immediately prior to the effective time under our equity compensation plans was cancelled and of no further force or effect as of the effective time. In exchange for the cancellation of the equity awards, each holder of such an equity award received from us the Cash Consideration for each share of Former Forestar Common Stock underlying such equity award (and in the case of equity awards that were stock options or stock appreciation rights, less the applicable exercise or strike price, but not less than $0), whether or not otherwise vested as of the effective time. With respect to any of our market-leveraged stock units, the number of shares of Former Forestar Common Stock subject to such equity awards were determined pursuant to the terms set forth in the applicable award agreements and based on a per share value equal to $17.75.

We paid our financial advisor a transaction fee of $5,595,000 which was expensed upon closing of the Merger. New Forestar Common Stock continues to be listed and traded on the New York Stock Exchange under the ticker symbol, “FOR.”

As of October 5, 2017, we are a majority-owned subsidiary of D.R. Horton, the largest homebuilder by volume in the United States for fifteen consecutive years. We are evaluating the impact of any potential changes in our accounting policies and related party transactions with D.R. Horton post merger and will update our disclosures accordingly in future periods. The merger will be accounted for under the acquisition method in accordance with U.S. GAAP. D.R. Horton is the acquirer for accounting purposes and our consolidated financial statements will continue to be stated at historical cost.

Letter of Credit Facility

On October 5, 2017, we entered into a Letter of Credit Facility Agreement (the “LC Facility Agreement”) providing for a $30,000,000 secured standby letter of credit facility (the “LC Facility”) with Keybank National Association and other lenders party thereto, as banks, Keybank National Association, as letter of credit issuer and administrative agent, and Keybanc Capital Markets, as sole arranger and sole bookrunner.

The LC Facility is secured by $30,000,000 in cash deposited with the administrative agent. We are required to pay a letter of credit fee of 1.25% per annum on the outstanding face amount of the letters of credit issued under the LC Facility, as well as other customary fees and expenses. We also are required to pay an unused facility fee of 0.15% per annum, in each case on the daily amount by which the aggregate commitments exceed the sum of the outstanding letters of credit during each fiscal quarter or portion thereof.

The LC Facility Agreement includes customary representations and warranties, affirmative and negative covenants and other undertakings. The LC Facility Agreement also contains customary events of default. If an event of default occurs, all or a portion of the commitments under the LC Facility may be terminated and/or other rights held by the banks under any of the related facility documents (including against the collateral) may be exercised, subject to certain limitations.

Termination of Senior Credit Facility

On October 5, 2017, in connection with entry into the LC Facility, we terminated our existing senior credit facility (the “Prior Credit Facility”). The Prior Credit Facility provided for a $50,000,000 revolving line of credit that was scheduled to mature on May 15, 2018. This Prior Credit Facility could be prepaid at any time without penalty and included a $50,000,000 sublimit for letters of credit, of which $14,267,000 were outstanding at the time of termination and were transferred to the new LC Facility.

3.75% Convertible Senior Notes

On October 5, 2017, in connection with the consummation of the Merger, we entered into a Third Supplemental Indenture (together with the base indenture and the prior supplemental indentures, the "Indenture") to the Indenture relating to our 3.75% Convertible Senior Notes due 2020 (the “Convertible Notes”).

Pursuant to the Third Supplemental Indenture, the Convertible Notes are no longer convertible into shares of Former Forestar Common Stock and instead are convertible into cash and shares of New Forestar Common Stock based on the per-share weighted average of the cash and shares of New Forestar Common Stock received by our stockholders that affirmatively made an election in connection with the Merger. As a result of such elections, for each share of Former Forestar Common Stock a holder of Convertible Notes was previously entitled to receive upon conversion of Convertible Notes, such holder is instead entitled to receive $14.19785 in cash and 0.20012 of a share of New Forestar Common Stock.

The completion of the Merger constituted a Fundamental Change, as defined in the Indenture. On October 12, 2017, in accordance with the Indenture, we gave notice of the Fundamental Change to holders of the Convertible Notes and made an offer to purchase (a “Fundamental Change Offer”) all or any part (equal to $1,000 or an integral multiple of $1,000) of every holder’s Convertible Notes pursuant to the Fundamental Change Offer on the terms set forth in the Indenture. In the Fundamental Change Offer, we offered to repurchase the Convertible Notes for a price in cash equal to 100% of the aggregate principal amount of Convertible Notes, plus accrued and unpaid interest, if any, to the date of repurchase.

Expiration of Tax Benefits Preservation Plan

On October 5, 2017 immediately prior to the effective time of the merger, our Tax Benefit Preservation Plan expired pursuant to its terms and all Rights previously distributed to the holders of our common stock pursuant to the Plan expired.

8.50% Senior Secured Notes

On October 30, 2017 (the “Redemption Date”), we redeemed the remaining $5,315,000 aggregate principal amount of outstanding 8.50% Senior Secured Notes due 2022 (the “Notes”). Pursuant to the indenture governing the Notes, the Notes were redeemed for $5,928,063, which was the sum of (a) the present value of 104.250% of the outstanding principal amount of the Notes and the scheduled payments of interest thereon through June 1, 2018 discounted as set forth in such indenture to the Redemption Date, plus (b) accrued and unpaid interest to but not including the Redemption Date.