Other Non-Operating Income (Details 1) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Schedule of Non-Operating Income (Expense) [Line Items]
Gain on sale of land	$ 0	$ 34,100	$ 0		$ 34,072	$ 0
Foreign currency loss, net	(3,797)		(12,972)		(33,324)	(16,191)
Gain (loss) on sales of businesses	0		(26,253)	$ 2,900	18,931	(23,335)
Loss on write-downs of cost method investments	(15,000)		(1,114)		(15,161)	(1,364)
Gain on sales of marketable equity securities (see Note 3)	0		0		6,256	0
Gain on formation of joint ventures	0		0		3,232	5,972
Additional gain on sale of Classified Ventures					0	4,827
Other, net	572		(119)		1,865	206
Total Other Non-Operating (Expense) Income	(18,225)		(40,458)		15,871	(29,885)
Classified Ventures LLC [Member]
Schedule of Non-Operating Income (Expense) [Line Items]
Additional gain on sale of Classified Ventures	$ 0		0		$ 0	$ 4,827
Education [Member]
Schedule of Non-Operating Income (Expense) [Line Items]
Gain (loss) on sales of businesses			$ 26,300

[Line Items] for Schedule of Non-Operating Income (Expense) [Table]

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The amount of the gain (loss) recognized by the parent and included in its attributable portion of net income for the period due to deconsolidation of a subsidiary or derecognition of a group of assets. The gain (loss) recognized and included in the net income attributable to the parent for the period is generally computed as the difference between: (a) the aggregate of: (1) the fair value of any consideration received; (2) the fair value of any retained noncontrolling investment in the former subsidiary at the date the subsidiary was deconsolidated; and (3) the carrying amount of any noncontrolling interest in the former subsidiary (including any accumulated other comprehensive income attributable to the noncontrolling interest) at the date the subsidiary was deconsolidated and (b) the carrying amount of the former subsidiary's assets and liabilities.

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Amount of gain (loss) on sale or disposal of an equity method investment.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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Amount of gain (loss) related to nonoperating activities, classified as other.

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