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Stock-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 USD ($) shares | Jun. 30, 2016 USD ($) | Jun. 30, 2017 USD ($) day $ / shares shares | Jun. 30, 2016 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock-based compensation expenses | $ |  |  | $ 13,823 | $ 12,979
Restricted Stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  |  | 3 years |
Stock granted (in shares) | shares |  |  | 1,588,010 |
Granted, weighted average grant date fair value per unit (in usd per share) | $ / shares |  |  | $ 15.24 |
Stock-based compensation expenses | $ | $ 4,900 | $ 4,900 | $ 10,300 | 10,700
Performance Share Units [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock granted (in shares) | shares |  |  | 509,800 |
Granted, weighted average grant date fair value per unit (in usd per share) | $ / shares |  |  | $ 16.89 |
Stock-based compensation expenses | $ | $ 2,200 | $ 1,300 | $ 3,500 | $ 2,200
Right to received shares of common stock (in shares) | shares | 1 |  | 1 |
Number of trading days | day |  |  | 30 |
Volatility assumption, volume weighted average stock price |  |  | 30 days |
Performance Share Units [Member] | Minimum [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
PSU granted percentage of earnings (as a percent) |  |  | 0.00% |
Performance Share Units [Member] | Maximum [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
PSU granted percentage of earnings (as a percent) |  |  | 200.00% |

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- Definition Percentage Of Performance Share Awards Based On Shareholder Return + References No definition available. + Details
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- Definition Rights Received For Each Performance Share Unit1 + References No definition available. + Details
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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Volume Weighted Average Consideration Period + References No definition available. + Details
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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 + Details
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (a)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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