Other Expenses - Schedule of General and Administrative Expenses (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Professional services	$ 4,437	$ 3,812	$ 3,311
Operating and other costs	2,938	1,903	2,147
Subtotal	7,375	5,715	5,458
Non-cash and CT Legacy Portfolio compensation expenses
Restricted class A common stock earned	27,654	23,593	19,052
Subtotal	28,154	24,031	22,089
Other expenses		176	169
General and administrative expenses	35,529	29,922	27,716
General and Administrative Expense [Member]
Non-cash and CT Legacy Portfolio compensation expenses
Director stock-based compensation	500	438	375
CT Legacy Partners [Member]
Non-cash and CT Legacy Portfolio compensation expenses
Management incentive awards plan			1,094
Manager [Member]
Non-cash and CT Legacy Portfolio compensation expenses
Management incentive awards plan	27,900	16,200	18,000
General and administrative expenses	$ 35,529	$ 29,746	27,547
CT Opportunity Partners I, LP [Member]
Non-cash and CT Legacy Portfolio compensation expenses
Management incentive awards plan			$ 1,568

Core, general and administrative expenses.

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General and administrative operating and other costs.

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

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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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