Share-Based and Long-Term Incentive Compensation - Components of Share-Based Compensation Expense (Income) (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	$ 1,416	$ 336	$ 2,259	$ 1,716
Compensation expense	32	76	84	240
Share based and Long Term Incentive Compensation	1,448	412	2,343	1,956
Cash Settled Awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	1,026	(494)	1,113	125
Equity-settled awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	285	625	903	1,104
Restricted Stock
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	0	6	0	12
Employee Stock Option
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	$ 105	$ 199	$ 243	$ 475

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=6415400&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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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=66902209&loc=d3e3602-108585

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