v3.7.0.1

Stock-Based Compensation - Summary of Share Based Compensation Expense (Detail) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2017 | Mar. 31, 2016
Stock-based compensation expense: |  |
Total stock-based compensation expense | $ 553 | $ 1,490
Time-based Restricted Units [Member] |  |
Stock-based compensation expense: |  |
Total stock-based compensation expense | $ 553 | 619
Performance-based Restricted Units [Member] |  |
Stock-based compensation expense: |  |
Total stock-based compensation expense |  | $ 871

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- Definition The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation. + 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 (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 + Details
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Balance Type: | debit
Period Type: | duration

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- References No definition available. + Details
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Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |