XML 114 R99.htm IDEA: XBRL DOCUMENT v3.6.0.2
Stock-Based Compensation Plans - Summarizes Transactions of SEUs (Detail) - Stock Equivalent Units [Member]
 12 Months Ended
Dec. 31, 2016
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Outstanding, Number of SEUs, Beginning balance | shares 279,750
Granted at discount, Number of SEUs | shares 70,153
Granted at market value, Number of SEUs | shares 7,316
Exercised, Number of SEUs | shares (66,424)
Forfeited, Number of SEUs | shares (10,980)
Outstanding, Number of SEUs, Ending balance | shares 279,815
Outstanding, Weighted Average Exercise Price, Beginning balance $ 3.79
Granted at discount, Weighted Average Exercise Price 0.00
Granted at market value, Weighted Average Exercise Price 44.18
Exercised, Weighted Average Exercise Price 4.32
Forfeited, Weighted Average Exercise Price 3.61
Outstanding, Weighted Average Exercise Price, Ending balance 3.77
Outstanding, Weighted Average Grant-Date Fair Value 31.72
Granted at discount, Weighted Average Grant-Date Fair Value 36.05
Granted at market value, Weighted Average Grant-Date Fair Value 9.11
Exercised, Weighted Average Grant-Date Fair Value 27.28
Forfeited, Weighted Average Grant-Date Fair Value 31.66
Outstanding, Weighted Average Grant-Date Fair Value $ 33.40