Investments in Affiliates (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016
Investments in and Advances to Affiliates [Line Items]
Investments in affiliates	$ 37,170	$ 35,668	$ 34,517
Joint Venture Unconsolidated
Investments in and Advances to Affiliates [Line Items]
Investments in affiliates	37,170	35,668	34,517
Equity Method Investment, Summarized Financial Information, Assets	156,969	155,506	176,275
Equity Method Investments Summarized Financial Information Net Assets	96,638	99,804	102,650
Equity Method Investments	22,200	20,800	19,400
Joint Venture Unconsolidated | Other Affiliates [Member]
Investments in and Advances to Affiliates [Line Items]
Investments in affiliates	9,841	9,757	9,499
Equity Method Investments	37,170	35,668	34,517
Joint Venture Unconsolidated | Equity Method investments in Real Estate Affiliates [Member]
Investments in and Advances to Affiliates [Line Items]
Investments in affiliates	27,329	$ 25,911	$ 25,018
Joint Venture Unconsolidated | Minimum [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Investments in and Advances to Affiliates [Line Items]
Investments in affiliates	21,600
Joint Venture Unconsolidated | Maximum | Real Estate Entities [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Investments in and Advances to Affiliates [Line Items]
Real Estate Development Projects Range of Total Assets	$ 70,700