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Stock-Based Compensation - Additional Information (Detail) (USD $) | 12 Months Ended |  | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2013 Minimum [Member] | Dec. 31, 2013 Maximum [Member] | Dec. 31, 2013 Performance Share Unit Awards [Member] | Dec. 31, 2012 Performance Share Unit Awards [Member] | Jul. 30, 2012 Performance Share Unit Awards [Member] | Dec. 31, 2013 Performance Share Unit Awards [Member] Minimum [Member] | Dec. 31, 2013 Performance Share Unit Awards [Member] Maximum [Member] | Dec. 31, 2013 Restricted stock awards [Member] | Dec. 31, 2012 Restricted stock awards [Member] | Dec. 31, 2011 Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares available for grant | 7,200,000 |  |  |  |  |  |  |  |  |  |  |  |
Annual Forfeiture Rate |  |  |  | 0.00% | 11.00% | 2.70% |  |  |  |  |  |  |
Expected percentage of PSUs earned | 112.00% | 98.00% |  |  |  |  |  |  |  |  |  |  |
Stock-based compensation expense | $ 11,982,000 | $ 10,333,000 | $ 3,656,000 |  |  | $ 1,800,000 | $ 400,000 |  |  |  | $ 10,200,000 | $ 10,200,000 | $ 3,700,000
Unrecognized expense |  |  |  |  |  | 6,800,000 |  |  |  |  | 24,800,000 |  |
Unrecognized expense recognition period, years |  |  |  |  |  | 2 years 11 months 2 days |  |  |  |  | 2 years |  |
Fair value of awards vested |  |  |  |  |  |  |  |  |  |  | 6,500,000 |  |
Right to received shares of common stock |  |  |  |  |  |  |  | 1 |  |  |  |  |
Performance share units initial performance period, years |  |  |  |  |  | 3 years |  |  |  |  |  |  |
PSU granted percentage of earnings |  |  |  |  |  |  |  |  | 0.00% | 200.00% |  |  |
Number of trading days |  |  |  |  |  | 30 days |  |  |  |  |  |  |
Common units granted in period |  |  |  |  |  | 135,620 | 155,220 |  |  |  | 594,895 | 753,285 |
Expected volatility rate |  |  |  |  |  | 47.48% | 51.00% |  |  |  |  |  |
Risk-free interest rate |  |  |  |  |  | 0.65% | 0.46% |  |  |  |  |  |
Expected liquidity term, years |  |  |  |  |  | 4 years | 4 years 0 months 2 days |  |  |  |  |  |
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense | $ 4,500,000 | $ 4,000,000 | $ 1,400,000 |  |  |  |  |  |  |  |  |  |

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- Definition Percentage Of Performance Share Awards Based On Shareholder Return + References No definition available. + Details
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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Output, Expected Percentage Earned + References No definition available. + Details
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- Definition Unrecognized cost of unvested share-based compensation awards. + 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. + 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 (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + 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=31042434&loc=d3e3602-108585 + 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=6415400&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Expected term of share-based compensation awards, 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 S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.D.2) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section D -Subsection 2 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + 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 (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + 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 (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + 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)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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