Debt instrument, maturity, month and year.

No definition available.

Name:	icon_DebtInstrumentMaturityMonthAndYear
Namespace Prefix:	icon_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3291-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_ConvertibleSubordinatedDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=icon_SeniorNotesOnePointFiveZeroPercentDueMarchTwentyEighteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=icon_SeniorNotesTwoPointFiveZeroPercentDueJuneTwentySixteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Schedule of Debt Obligations (Parenthetical) (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Mar. 18, 2013	May. 23, 2011
Debt Instrument [Line Items]
Payment of debt transaction costs	$ 9,600
Convertible Notes \| 1.50% Senior Subordinated Notes Due March 15, 2018
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	1.50%	1.50%	1.50%	1.50%
Convertible Notes \| 2.50% Senior Subordinated Notes Due June 2016
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	2.50%	2.50%	2.50%		2.50%
Debt instrument, Maturity Date	2016-06