Share-Based and Long-Term Incentive Compensation - Components of Share-Based Compensation Expense (Income) (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	$ 308	$ 949	$ 2,567	$ 2,665
Compensation expense	116	75	200	315
Share based and Long Term Incentive Compensation	424	1,024	2,767	2,980
Cash Settled Awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	(66)	(43)	1,047	82
Equity-settled awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	268	765	1,171	1,869
Restricted Stock
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	0	10	0	22
Employee Stock Option
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	$ 106	$ 217	$ 349	$ 692

Share Based and Long Term Incentive Compensation

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- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

+ References

Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363

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- 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.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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