Amount of gain associated with mark-to-market adjustments.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ 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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2420-110228

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 45

-Paragraph 1

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- Definition

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 2

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-Publisher FASB

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-Section 25

-Paragraph 1

-Subparagraph (c)

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- Definition

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity, not expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

+ References

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- Definition

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 13

-Paragraph Column C

-Article 12

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 14

-Paragraph Column E

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

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-Topic 946

-SubTopic 320

-Section S99

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 5

-Subparagraph (SX 210.12-13.Column C.6)

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-Publisher SEC

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 12C

-Paragraph Column C

-Article 12

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- Definition

The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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-Publisher FASB

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-Topic 360

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-Section 50

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Fair Value Measurements - Narrative (Detail) (USD $)	12 Months Ended
Fair Value Measurements - Narrative (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Marketable securities, current	$ 25,263,000us-gaap_HeldToMaturitySecuritiesCurrent	$ 38,250,000us-gaap_HeldToMaturitySecuritiesCurrent
Marketable securities, non current	19,365,000	6,088,000
Equity method investments	135,989,000us-gaap_EquityMethodInvestments	110,638,000us-gaap_EquityMethodInvestments
Private equity funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity method investments	1,128,000	1,766,000
Impairment charges	100,000	300,000	400,000
Private equity funds [Member] \| Level 3 [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair market value of investment	1,600,000
Penn Mezzanine [Member]
Schedule of Available-for-sale Securities [Line Items]
Amount of gain associated with mark-to-market adjustments		1,100,000
Impairment charges		300,000	2,500,000
Penn Mezzanine [Member] \| Equity loss [Member]
Schedule of Available-for-sale Securities [Line Items]
Impairment charges		1,800,000
PixelOptics, Inc. [Member]
Schedule of Available-for-sale Securities [Line Items]
Asset Impairment Charges		11,200,000	5,000,000
Equity method investments	$ 0