Stock-Based Compensation - Fair Value Assumptions (Details) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) item $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares
Additional information
Accrued compensation	$ 61,712	$ 54,079
Allocated Share-based Compensation Expense	$ 5,000	$ 5,600	$ 4,800
Stock Options
Stock-Based Compensation
Weighted-average fair value per share of options granted (in dollars per share) | $ / shares	$ 9.94	$ 6.33	$ 6.24
Fair value assumptions:
Expected dividend yield (as a percent)	0.97%	1.51%	1.34%
Expected stock price volatility (as a percent)	37.90%	38.40%	45.20%
Risk-free interest rate (as a percent)	1.41%	1.50%	1.91%
Expected term	5 years 3 months 18 days	5 years 7 months 6 days	5 years 7 months 6 days
Other information
Vesting period	3 years
Total fair value of options vested	$ 900
Nonvested Options, Shares
Nonvested at beginning of year (in shares) | shares	287
Granted (in shares) | shares	102
Vested (in shares) | shares	(148)
Nonvested at end of year (in shares) | shares	241	287
Nonvested Options, Weighted-Average Grant Date Fair Value
Nonvested at beginning of year (in dollars per share) | $ / shares	$ 6.07
Granted (in dollars per share) | $ / shares	9.94	$ 6.33	$ 6.24
Vested (in dollars per share) | $ / shares	5.85
Nonvested at end of year (in dollars per share) | $ / shares	$ 7.83	$ 6.07
Additional information
Compensation expense yet to be recognized	$ 800
Weighted-average period over which compensation cost will be recognized	1 year 6 months
Stock Options | Minimum
Other information
Sum of age and years of service for accelerated vesting on retirement of certain stock options and restricted stock awards	75 years
Restricted Stock and Restricted Stock Units
Shares
Unvested at beginning of year (in shares) | shares	149
Granted (in shares) | shares	85
Vested (in shares) | shares	(108)
Unvested at end of year (in shares) | shares	126	149
Weighted Average Grant Date Fair Value
Unvested at beginning of year (in dollars per share) | $ / shares	$ 17.48
Granted (in dollars per share) | $ / shares	30.25	$ 20.64	15.80
Vested (in dollars per share) | $ / shares	20.61
Unvested at end of year (in dollars per share) | $ / shares	$ 23.41	17.48
Additional information
Compensation expense yet to be recognized	$ 1,300
Weighted-average period over which compensation cost will be recognized	1 year 7 months 6 days
Fair value of shares vested	$ 2,200
Weighted-average fair value (in dollars per share) | $ / shares	$ 30.25	$ 20.64	$ 15.80
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested	$ 3,600	$ 3,400	$ 2,900
Performance Stock Units
Other information
Vesting period	3 years
Additional information
Compensation expense yet to be recognized	$ 1,500
Weighted-average period over which compensation cost will be recognized	1 year 1 month 6 days
Period for which shareholder return is compared with peer group for units determined by EPS performance	3 years
Types of performance units | item	2
Percentage of units measured on stock price relative to peer group	50.00%
Percentage of units measured on stock price based on pre determined EPS	50.00%
Calculated fair market value	$ 4,800
Value of PSUs granted	1,800
Allocated Share-based Compensation Expense	$ 1,600	$ 2,600	$ 1,800
Performance Stock Units | Minimum
Additional information
Performance measures for dollar denominated award granted	0
Performance Stock Units | Maximum
Additional information
Performance measures for dollar denominated award granted	2.0
Restricted Stock | Minimum
Other information
Sum of age and years of service for accelerated vesting on retirement of certain stock options and restricted stock awards	75 years