Defined Contribution Plans	6 Months Ended
Jun. 30, 2017
Retirement Benefits [Abstract]
Defined Contribution Plans	DEFINED CONTRIBUTION PLANS ESA Management has a savings plan that qualifies under Section 401(k) of the Code for all employees meeting the eligibility requirements of the plan. For the period from January 1, 2016 through September 9, 2016, the plan had an employer-matching contribution of 100% of the first 3% of an employee's contribution and 50% of the next 2% of an employee's contribution, which vested immediately. Beginning January 1, 2017, the plan has an employer-matching contribution of 50% of the first 6% of an employee's contribution, which vests over an employee's initial three-year service period. The plan also provides for contributions up to 100% of eligible employee pretax salary, subject to the Code’s annual deferral limit of $18,000 during 2017 and 2016. Employer contributions, net of forfeitures, totaled approximately $0.5 million and $0.8 million for the three months ended June 30, 2017 and 2016, respectively, and approximately $0.8 million and $1.9 million for the six months ended June 30, 2017 and 2016, respectively. In June 2016, ESA Management established a non-qualified deferred compensation plan to allow certain eligible employees an option to defer a portion of their compensation on a tax-deferred basis. Beginning January 2017, the plan had an employer-matching contribution of 50% of the first 6% of an employee's contribution, which vests over a three-year service period. The plan is fully funded in a Rabbi Trust, which is subject to creditor claims in the event of insolvency, but the assets held in the Rabbi Trust are not available for general corporate purposes. As of June 30, 2017, approximately $0.5 million is included in other assets and accounts payable and accrued liabilities related to this plan.

DEFINED CONTRIBUTION PLANS

ESA Management has a savings plan that qualifies under Section 401(k) of the Code for all employees meeting the eligibility requirements of the plan. For the period from January 1, 2016 through September 9, 2016, the plan had an employer-matching contribution of 100% of the first 3% of an employee's contribution and 50% of the next 2% of an employee's contribution, which vested immediately. Beginning January 1, 2017, the plan has an employer-matching contribution of 50% of the first 6% of an employee's contribution, which vests over an employee's initial three-year service period. The plan also provides for contributions up to 100% of eligible employee pretax salary, subject to the Code’s annual deferral limit of $18,000 during 2017 and 2016. Employer contributions, net of forfeitures, totaled approximately $0.5 million and $0.8 million for the three months ended June 30, 2017 and 2016, respectively, and approximately $0.8 million and $1.9 million for the six months ended June 30, 2017 and 2016, respectively.

In June 2016, ESA Management established a non-qualified deferred compensation plan to allow certain eligible employees an option to defer a portion of their compensation on a tax-deferred basis. Beginning January 2017, the plan had an employer-matching contribution of 50% of the first 6% of an employee's contribution, which vests over a three-year service period. The plan is fully funded in a Rabbi Trust, which is subject to creditor claims in the event of insolvency, but the assets held in the Rabbi Trust are not available for general corporate purposes. As of June 30, 2017, approximately $0.5 million is included in other assets and accounts payable and accrued liabilities related to this plan.