Amount of gain (loss) on sale of disposal of building.

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This item represents the total realized gain included in earnings for the period as a result of exchanging marketable securities.

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Amount of effect on financial statements related to corrections of prior period errors in the current period financial statements when the effect of the prior period error was immaterial to the prior period financial statements and the current period correction is immaterial to the current period financial statements.

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No definition available.

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The number of businesses disposed of by the entity during the period.

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No definition available.

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Number of shares exchanged in a transaction.

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The total cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence, including amount held in escrow and to be received at a later date.

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No definition available.

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[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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 50
-Paragraph 1
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 1B
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 3
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Amount of gain (loss) on sale or disposal of an equity method investment.

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No definition available.

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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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No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Other Non-Operating (Expense) Income (Narrative) (Details) $ in Thousands				1 Months Ended		3 Months Ended							12 Months Ended
	Oct. 01, 2014 USD ($)	Jun. 30, 2014 USD ($) shares	Mar. 27, 2014 USD ($)	Jun. 30, 2016 USD ($)	Jan. 31, 2015 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Jun. 30, 2015 USD ($) business	Dec. 31, 2014 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014
Schedule of Non-Operating (Expense) Income [Line Items]
Gain on sale of property, plant and equipment								$ 34,100		$ 21,400			$ 34,072	$ 21,379	$ 127,670
Gain (loss) on sale of business											$ 2,900		18,931	(23,335)	0
Gain on formation of a joint venture													3,232	5,972	0
Gain on sale of an equity affiliate													0	4,827	396,553
Gain on share exchange													0	0	266,733
Proceeds from sale of headquarters building			$ 158,000
Gain on sale of headquarters building			$ 127,700
Education [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Gain (loss) on sale of business						$ (26,300)
Number Of Businesses Disposed \| business											2
Residential Healthcare Group Inc [Member] \| Residential And Michigan Hospital Joint Venture [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Ownership percentage of investment in affiliate				40.00%				40.00%
Gain on formation of a joint venture				$ (3,200)
Classified Ventures LLC [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Favorable out of period adjustment											$ 4,800
Gain on sale of an equity affiliate													$ 0	$ 4,827	$ 396,553
Celtic Healthcare Inc [Member] \| Celtic Healthcare Allegheny Health Network Joint Venture [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Gain on formation of a joint venture					$ 6,000
Berkshire Hathaway Inc [Member] \| Berkshire Exchange Transaction [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Gain on share exchange		$ 266,700
Berkshire Hathaway Inc [Member] \| Class B Common Stock [Member] \| Berkshire Exchange Transaction [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Number of shares exchanged \| shares		1,278
Berkshire Hathaway Inc [Member] \| Common Class A [Member] \| Berkshire Exchange Transaction [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Number of shares exchanged \| shares		2,107
Classified Ventures LLC [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Ownership percentage of investment in affiliate																16.50%
Proceeds from sale of equity method investment, including amount held in escrow	$ 408,500
Proceeds from sale of equity method investment										$ 16,500
Gain on sale of an equity affiliate												$ 396,600
Celtic Healthcare Allegheny Health Network Joint Venture [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Ownership percentage of investment in affiliate					40.00%
Celtic Healthcare Allegheny Health Network Joint Venture [Member] \| Celtic Healthcare Inc [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Ownership percentage of investment in affiliate					40.00%	40.00%							40.00%
Vocational School Company [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Write-downs of cost method investment						$ (12,000)	$ (15,000)						$ (27,000)
Kaplan Corporate and Other [Member] \| Colloquy [Member] \| Education [Member]
Schedule of Non-Operating (Expense) Income [Line Items]
Gain (loss) on sale of business									$ 18,900