Stock Based Compensation - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013 Plans	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Stock Incentive Plans	5
Shares authorized under Stock Incentive Plans	11,500,000
Shares available under Stock Incentive Plans	373,243
Matching contributions in 401(k) / profit sharing plan	$ 300	$ 284	$ 197
Restricted stock and unit awards to employees	1,003,421
Fair value of restricted stock and unit awards	4,719	7,065	3,248
Compensation expense recognized at date of grant	1,008	3,649
Amortization related to restricted stock and unit awards	6,202	8,559	3,759
Amortization capitalized in development activities	43	32	0
Unrecognized compensation related to unvested restricted stock and unit awards	7,319
Weighted average period of unrecognized compensation expected to be recognized	10 months 0 days
Long-Term Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock and unit awards to employees	718,960
LTIP Unit Awards fair value	$ 5,411
Long-Term Incentive Program [Member] \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage by which maximum shares Issuable to Participant for Performance Period Multiplied	0.00%
Long-Term Incentive Program [Member] \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage by which maximum shares Issuable to Participant for Performance Period Multiplied	100.00%
Restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock and unit awards to employees	284,461	565,137	292,339
Restricted stock [Member] \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of restricted stock	3 years

Fair value at the date of grant of restricted stock and unit awards issued during the period.

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- Definition

Number Of Stock Incentive Plans

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- Definition

Percentage by Which Maximum Shares Issuable to Participant for Performance Period

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Fair Value

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No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ 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)

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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The amount of payment into the fund established for purposes of making future disbursements to the individual in accordance with the terms and understanding of the deferred compensation arrangement.

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No definition available.

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- Definition

Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

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No definition available.

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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.

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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).

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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).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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