Capital Structure - Additional Information (Detail)		3 Months Ended
	Feb. 28, 2017 USD ($)	Mar. 31, 2017 USD ($) ClassOfCommonStock $ / shares shares	Mar. 31, 2016 USD ($) $ / shares shares	Dec. 30, 2014 USD ($)
Equity, Class of Treasury Stock [Line Items]
Number of classes of common stock outstanding | ClassOfCommonStock		1
Acquisition of restricted stock from employees in connection with withholding tax payments (in shares) | shares		62,784	14,548
Withholding tax payments related to the vesting of restricted stock for total consideration		$ 2,913,000	$ 652,000
Weighted average purchase price per share prior to the vesting date (in dollars per share) | $ / shares		$ 46.39	$ 44.83
2014 Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock authorized by board of directors up to				$ 20,000,000
Stock repurchase program, period start (year)		2015
Stock repurchase program, period end (year)		2017
Common stock shares purchased under the repurchase program (in shares) | shares		193,962	138,638
Common stock aggregate purchase price including commissions		$ 9,000,000	$ 6,202,000
Common stock average purchase price per share (in dollars per share) | $ / shares		$ 46.40	$ 44.74
2017 Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock authorized by board of directors up to	$ 100,000,000
Stock repurchase program, period start (year)	2017
Stock repurchase program, period end (year)	2019
Authorized increase in repurchase amount, 2018	$ 40,000,000
Authorized increase in repurchase amount, 2019	40,000,000
Minimum | 2017 Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Authorized increase in repurchase amount	20,000,000
Maximum | 2017 Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Authorized increase in repurchase amount	$ 40,000,000