Share Based Compensation - Components of Share-Based Compensation Expense (Income) (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	$ 1,380	$ 3,342
Compensation expense	164	116
Share based and Long Term Incentive Compensation	1,544	3,458
Cash Settled Awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	619	296
Equity-settled awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	479	1,997
Restricted Stock
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	6	17
Employee Stock Option
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Total share-based compensation	276	1,032
General and Administrative Expense
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share based and Long Term Incentive Compensation	1,506	2,122
Other Operating Expenses
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share based and Long Term Incentive Compensation	$ 38	$ 1,336

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=56944662&loc=d3e3602-108585

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