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Variable Interest Entities, Contingent Liabilities and Consolidated Joint Ventures - MCB Real Estate, LLC (Details)	3 Months Ended
	Mar. 31, 2018 USD ($) item	Jan. 31, 2018	Dec. 31, 2017 USD ($)
Property located in Fort Bend, Texas
Consolidated VIEs Carrying Amount of Assets and Liabilities
Ownership percentage		85.00%
Consolidated JV
Consolidated VIEs Carrying Amount of Assets and Liabilities
Number of joint ventures with controlling interest	5
MCB Real Estate LLC And Its Affiliates | Consolidated JV
Consolidated VIEs Carrying Amount of Assets and Liabilities
Number of joint ventures with controlling interest	4
Investment in consolidated joint ventures | $	$ 9,604,000		$ 9,705,000

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+ References

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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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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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