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Variable Interest Entities, Contingent Liabilities and Consolidated Joint Ventures - MCB Real Estate, LLC (Details) - Consolidated JV	6 Months Ended
	Jun. 30, 2018 USD ($) item	Jan. 30, 2018	Dec. 31, 2017 USD ($)
Consolidated VIEs Carrying Amount of Assets and Liabilities
Number of joint ventures with controlling interest	5
Property located in Fort Bend, Texas | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Consolidated VIEs Carrying Amount of Assets and Liabilities
Ownership interest in consolidated joint venture of the company (as a percent)		85.00%
MCB Real Estate LLC And Its Affiliates
Consolidated VIEs Carrying Amount of Assets and Liabilities
Number of joint ventures with controlling interest	4
Investment in consolidated joint ventures | $	$ 9,734,000		$ 9,705,000

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- Definition

The carrying amount of investments in consolidated real estate and other joint ventures not separately presented. This includes direct and indirect investments.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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