Stock-Based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Number of shares available for grant (in shares)	8,550,000
Stock-based compensation expense	$ 25,272,000	$ 21,302,000	$ 11,982,000
Associated tax benefit	$ 8,700,000	8,400,000	4,500,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual forfeiture rate	0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual forfeiture rate	16.90%
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Stock-based compensation expense	$ 21,400,000	18,200,000	10,200,000
Fair value of awards vested	$ 9,500,000	$ 18,300,000	$ 6,500,000
Weighted average grant date fair value of awards granted (in dollars per share)	$ 14.28	$ 42.55	$ 38.64
Unrecognized expense	$ 29,300,000
Unrecognized expense recognition period	1 year 8 months 12 days
Performance share unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 3,900,000	$ 3,100,000	$ 1,800,000
Fair value of awards vested	$ 800,000	$ 0	$ 0
Weighted average grant date fair value of awards granted (in dollars per share)	$ 11.20	$ 41.71	$ 42.01
Unrecognized expense	$ 8,700,000
Unrecognized expense recognition period	2 years 2 months 12 days
Right to received shares of common stock	1
Performance share units initial performance period	3 years
Grant date fair value amortization term	4 years	4 years	4 years
Number of trading days	30 days
Expected percentage of PSUs earned	86.00%	98.00%	112.00%
Performance share unit awards \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual forfeiture rate	2.40%
PSU granted percentage of earnings	0.00%
Performance share unit awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual forfeiture rate	4.90%
PSU granted percentage of earnings	200.00%

The rate of forfeitures assumptions that is used in calculating the fair values of a share-based compensation award.

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Number Of Trading Days Consider For Average Closing Price

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- Definition

Percentage Of Performance Share Awards Based On Shareholder Return

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- Definition

Rights Received For Each Performance Share Unit1

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No definition available.

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- Definition

The initial performance period for the performance share units.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Output, Expected Percentage Earned

+ References

No definition available.

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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

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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.

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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.

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-Name Accounting Standards Codification
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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)
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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=6415400&loc=d3e5070-113901

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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
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-SubTopic 10
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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
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- Definition

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.

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No definition available.

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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
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-Paragraph 2
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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)
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