Share-Based Compensation - Additional Information (Detail) (Restricted Stock [Member], USD $) In Millions, except Share data in Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of restricted stock granted to certain eligible individuals under the amended and restated equity incentive plan	80
Unrecognized compensation cost related to restricted stock	$ 0.5
Weighted-average years to recognize compensation expense	10 months 24 days
Equity Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of restricted stock granted to certain eligible individuals under the amended and restated equity incentive plan	80
Vesting period	3 years
Equity Incentive Plans [Member] | Independent Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of restricted stock granted to certain eligible individuals under the amended and restated equity incentive plan	24
Equity Incentive Plans [Member] | Independent Directors [Member] | Immediately Vest [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of restricted stock granted to certain eligible individuals under the amended and restated equity incentive plan	14
Equity Incentive Plans [Member] | Independent Directors [Member] | Vest Over Next 9 Months [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of restricted stock granted to certain eligible individuals under the amended and restated equity incentive plan	10
Vesting period	9 months