Percentage of financial targets to be achieved for participants to receive award.

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ 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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Data Type:	xbrli:stringItemType
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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-Based Compensation - Restricted Stock Awards with Performance Conditions Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized equity-based compensation	$ 5,736	$ 13,421	$ 5,736	$ 13,421
Restricted stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized equity-based compensation	5,440	12,790	5,440	12,790
Restricted stock \| Performance based awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation expense	900	$ 200	2,700	$ 2,100
Unrecognized equity-based compensation	$ 900		$ 900
Minimum \| Restricted stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of target bonus potentially payable in restricted stock			100.00%
Maximum \| Restricted stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of target bonus potentially payable in restricted stock			150.00%