Stock Based Compensation (Narrative) (Detail)	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric for performance based restricted stock units	100.00%
Performance metric for performance based restricted stock units minimum potential range	0.00%
Performance metric for performance based restricted stock units maximum potential range	200.00%
2014 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under plan	6,100,000
Number of shares available for grant	6,096,349
ESPP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under plan	2,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	23,105
SIP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under plan	750,000
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	2,737
Minimum \| 2014 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Reduction in Shares Available for Grant per Share Issued	1
Maximum \| 2014 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Reduction in Shares Available for Grant per Share Issued	3.8
Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Shares	1,013
Performance And Market-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Shares	56,625
Performance And Market-Based Restricted Stock Units \| Senior management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric, minimum	0.00%
Performance metric, maximum	150.00%
Market-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Shares	1,875	76,175

Performance-based restricted stock units, performance metric, maximum potential range.

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Performance-based restricted stock units, performance metric, minimum potential range.

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Performance Metric For Performance Based Restricted Stock Units Maximum Potential Range

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Reduction in Shares Available for Grant per Share Issued

+ References

No definition available.

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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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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ 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)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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