Quarterly report pursuant to Section 13 or 15(d)

Schedule of Stock Activity Related to Share-Based Compensation (Detail)

v2.4.0.6
Schedule of Stock Activity Related to Share-Based Compensation (Detail)
 3 Months Ended
Mar. 31, 2013
Restricted Stock
  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Awards expected to vest by period 43,687
Restricted Stock | 2013
  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Awards expected to vest by period 27,297 [1]
Restricted Stock | 2014
  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Awards expected to vest by period 10,295
Restricted Stock | 2015
  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Awards expected to vest by period 6,095
Restricted Stock Units (RSUs)
  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Awards expected to vest by period 959,698
Restricted Stock Units (RSUs) | 2013
  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Awards expected to vest by period 474,812
Restricted Stock Units (RSUs) | 2014
  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Awards expected to vest by period 344,288
Restricted Stock Units (RSUs) | 2014 | Subject to Adjustments
  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Awards expected to vest by period 140,598 [2]
[1] Includes accelerated vesting of restricted shares held by one non-employee director who did not stand for re-election to the Board.
[2] In addition to service requirements, these RSUs are also subject to certain performance requirements not yet measureable, with adjustments ranging from 0% to 150%.