Merger	12 Months Ended
Dec. 31, 2017
Business Combinations [Abstract]
Merger	Merger On October 5, 2017, we merged with a subsidiary of D.R. Horton and we continued as the surviving entity (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. In connection with merger activities, we incurred $43,819,000 in transaction costs in 2017, of which, $41,475,000 are included in general and administrative expenses and $2,344,000 in other operating expenses on our consolidated statements of income (loss). These costs include a $20,000,000 merger termination fee paid to Starwood Capital Group, $7,683,000 in executive severance and change in control costs, $7,170,000 in transaction and other fees paid to our financial advisor, $4,617,000 in professional services and other costs and $4,349,000 related to the acceleration of vesting and settlement of equity awards.

Merger

On October 5, 2017, we merged with a subsidiary of D.R. Horton and we continued as the surviving entity (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.

In connection with merger activities, we incurred $43,819,000 in transaction costs in 2017, of which, $41,475,000 are included in general and administrative expenses and $2,344,000 in other operating expenses on our consolidated statements of income (loss). These costs include a $20,000,000 merger termination fee paid to Starwood Capital Group, $7,683,000 in executive severance and change in control costs, $7,170,000 in transaction and other fees paid to our financial advisor, $4,617,000 in professional services and other costs and $4,349,000 related to the acceleration of vesting and settlement of equity awards.