Share-Based Plans (Narrative) (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized	10,900,000
Number of common shares available for grant	1,300,000
Vesting period (in years)	1 year
Options granted, Number of Shares	377,598	0
Weighted average grant date fair value (in dollars per share)			$ 10.96
Expected term (in years)			6 years 10 months 24 days
Expected dividend rate (as a percent)			1.80%
Expected forfeiture rate (as a percent)			10.00%
Expected volatility (as a percent)			58.97%
Risk-free interest rate (as a percent)			1.36%
Weighted-average remaining contractual term for options expected to vest (in years)	7 years 2 months 12 days
Aggregate intrinsic value of options outstanding, options exercisable, and options expected to vest	$ 22.5	$ 21.0	$ 1.5
Total intrinsic value of options exercised	$ 4.3	1.9	1.8
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock, Granted (in shares)	0
Time Based Restricted Stock Awards [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	1 year
Time Based Restricted Stock Awards [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	5 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock, Granted (in shares)	223,190
Fair value of restricted stock awards	$ 11.6	$ 9.4	$ 5.1
Restricted Stock [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares available for grant	100,000
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock, Granted (in shares)	138,591
Vesting period (in years)	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%
Performance Shares [Member] | Minimum [Member] | Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%	0.00%
Performance Shares [Member] | Minimum [Member] | Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%
Performance Shares [Member] | Maximum [Member] | Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	150.00%	150.00%
Performance Shares [Member] | Maximum [Member] | Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	200.00%
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum contractual term (in years)	10 years
Options granted, Number of Shares	0
Number of options outstanding (in shares)	1,527,074	1,900,144
Employee Stock Option [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Employee Stock Option [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years
Non-Qualified Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding (in shares)	1,388,957
Incentive Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding (in shares)	138,117