Stockholders' Equity and EPS - Common Shares Excluded from Diluted EPS Calculation as They Were Deemed to be Anti-Dilutive (Detail) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from diluted earnings per share calculation	73	605	36	495
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from diluted earnings per share calculation	73	462	36	407
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from diluted earnings per share calculation	0	143	0	88