Capital Structure - Additional Information (Details)			3 Months Ended		6 Months Ended
	Feb. 28, 2017 USD ($)	Dec. 30, 2014 USD ($)	Jun. 30, 2017 USD ($) $ / shares shares	Jun. 30, 2016 USD ($) $ / shares shares	Jun. 30, 2017 USD ($) ClassOfCommonStock $ / shares shares	Jun. 30, 2016 USD ($) $ / shares shares
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			2,219	1,479	65,003	16,027
Withholding tax payments related to the vesting of restricted stock for total consideration			$ 103,000	$ 76,000	$ 3,016,000	$ 728,000
Weighted average purchase price per share prior to the vesting date (in dollars per share) | $ / shares			$ 46.51	$ 51.39	$ 46.40	$ 45.44
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				56,172		194,810
Common stock aggregate purchase price including commissions				$ 2,773,000		$ 8,975,000
Common stock average purchase price per share (in dollars per share) | $ / shares				$ 49.37		$ 46.07
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
2014 and 2017 Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Common stock shares purchased under the repurchase program (in shares) | shares			230,022		423,984
Common stock aggregate purchase price including commissions			$ 11,316,000		$ 20,316,000
Common stock average purchase price per share (in dollars per share) | $ / shares			$ 49.20		$ 47.92
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