Investments Investments Table (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value Measurement [Domain]
Schedule of Cost and Equity Method Investments [Line Items]
Equity method investments	$ 77,484	$ 82,584
Available-for-sale securities	26,784	27,482
Cost method investments	25,236	31,816
Total investments	$ 129,504	$ 141,882
Maximum [Member]
Schedule of Cost and Equity Method Investments [Line Items]
Available-for-Sale Securities, Ownership Percentage	25.00%	25.00%
Cost Method Investments, Ownership Percentage	19.00%	19.00%
Equity Method Investments, Ownership Percentage	24.00%
Minimum [Member]
Schedule of Cost and Equity Method Investments [Line Items]
Available-for-Sale Securities, Ownership Percentage	19.00%	19.00%
Cost Method Investments, Ownership Percentage	1.00%	1.00%
Equity Method Investments, Ownership Percentage	10.00%	41.00%
Convertible debt securities [Member]
Schedule of Cost and Equity Method Investments [Line Items]
Available-for-sale securities	$ 11,232	$ 10,038
Redeemable preferred shares [Member]
Schedule of Cost and Equity Method Investments [Line Items]
Available-for-sale securities	$ 15,552	$ 17,444

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