Cost method investment ownership percentage.

No definition available.

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- Definition

Cost Method Investments, Increase from Exercise of Warrants

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Other activity regarding equity transfers among controlling entity (ACTUA) and noncontrolling owners.

+ References

No definition available.

+ Details

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- Definition

Proceeds from cost method investment.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

+ 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)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=29638308&loc=d3e40346-111594

+ Details

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Period Type:	instant

- Definition

For investments in debt and equity securities accounted for at cost, the excess of net sale proceeds over the carrying amount of investments disposed of during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(7)(c))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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
-URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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Equity and Cost Method Businesses - Cost Method Businesses Additional Information (Detail) - USD ($)		12 Months Ended
	Mar. 10, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Cost-method Investments [Line Items]
Cost method businesses		$ 17,250,000	$ 18,146,000
Carrying value of holdings in cost method companies			18,100,000
Impact of subsidiary equity transactions		5,719,000	(4,803,000)	$ 1,658,000
Gain from cost method investment		2,800,000
Impairment of cost method investment		0	0	$ 0
Anthem
Schedule of Cost-method Investments [Line Items]
Carrying value of holdings in cost method companies		$ 0
Fair value of active common stock remaining		9.00%
Proceeds from cost method investment			1,000,000
Gain from cost method investment			$ 1,000,000
Anthem \| Subsequent Event
Schedule of Cost-method Investments [Line Items]
Proceeds from cost method investment	$ 866,000
Parchment
Schedule of Cost-method Investments [Line Items]
Impact of subsidiary equity transactions		$ 700,000
InstaMed
Schedule of Cost-method Investments [Line Items]
Adjustment to cost method investment		(1,600,000)
Gain from cost method investment		$ 2,800,000