Other Expenses - Schedule of General and Administrative Expenses (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Professional services	$ 862	$ 756	$ 1,878	$ 1,644
Operating and other costs	489	521	934	1,391
Subtotal	1,351	1,277	2,812	3,035
Non-cash and CT Legacy Portfolio compensation expenses
Restricted class A common stock earned	5,865	4,742	11,678	9,335
Subtotal	5,959	5,463	11,866	10,449
Other expenses	63	41	122	92
General and administrative expenses	7,373	6,781	14,800	13,576
General and Administrative Expense [Member]
Non-cash and CT Legacy Portfolio compensation expenses
Director stock-based compensation	94	94	188	188
Manager [Member]
Non-cash and CT Legacy Portfolio compensation expenses
Management incentive awards plan	4,800	6,400	8,200	10,600
General and administrative expenses	$ 7,310	6,740	$ 14,678	13,484
CT Legacy Partners [Member]
Non-cash and CT Legacy Portfolio compensation expenses
Management incentive awards plan		630		758
CT Opportunity Partners I, LP [Member]
Non-cash and CT Legacy Portfolio compensation expenses
Management incentive awards plan		$ (3)		$ 168

Core, general and administrative expenses.

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General and administrative operating and other costs.

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Non cash and legacy compensation expenses.

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Stock Based Non Cash Compensation Expenses [Abstract]

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount of expense for incentive rights held by the managing member or general partner, of limited liability company (LLC) or limited partnership (LP).

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Amount of general and administrative expense classified as other.

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A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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