XML 91 R77.htm IDEA: XBRL DOCUMENT v3.8.0.1
Share-Based Compensation - Schedule of Deferred Stock Units to be Settled in Shares (Detail) - $ / shares
 12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]      
Beginning balance of Outstanding, Deferred Stock Units to be Settled in Shares 76,023 [1] 90,642 [1] 116,952
Granted, Deferred Stock Units to be Settled in Shares 0 0 2,928
Vested, Deferred Stock Units to be Settled in Shares 0 (14,619) (19,492)
Forfeited, Deferred Stock Units to be Settled in Shares 0 0 (9,746)
Ending balance of Outstanding, Deferred Stock Units to be Settled in Shares [1] 76,023 76,023 90,642
Beginning balance of Outstanding, Weighted Average Grant-Date Fair Value Per Unit $ 4.44 [1] $ 4.43 [1] $ 4.39
Granted, Weighted Average Grant-Date Fair Value Per Unit 0 0 5.73
Vested, Weighted Average Grant-Date Fair Value Per Unit 0 4.39 4.39
Forfeited, Weighted Average Grant-Date Fair Value Per Unit 0 0 4.39
Ending balance of Outstanding, Weighted Average Grant-Date Fair Value Per Unit [1] $ 4.44 $ 4.44 $ 4.43
[1] Includes vested but unreleased awards. These awards are included in total outstanding awards until they are released under the terms of the agreement.