Stock-Based Compensation (Detail) - Stock-Based Compensation Expense By Award Type (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 6,900,000	[1],[2]	$ 7,200,000	[1],[2]	$ 20,600,000	[1],[2]	$ 19,574,000	[1],[2]
Stock-based compensation expense reversal forfeited awards	1,900,000				1,900,000
Retirement eligible employees equity award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	2,100,000		1,700,000		9,800,000		8,800,000
Stock appreciation rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1,000,000		1,200,000		2,900,000		3,000,000
Common stock equivalents (CSEs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	200,000		100,000		300,000		300,000
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 5,700,000		$ 5,900,000		$ 17,400,000		$ 16,300,000

[1] The three and six months ended June 30, 2014 include a reversal of $1.9 million of expense from forfeited awards related to the departure of the Company's former CFO.

[2] Includes charges of $2.1 million and $1.7 million for the three months ended June 30, 2014 and 2013, respectively, and $9.8 million and $8.8 million for the six months ended June 30, 2014 and 2013, respectively, for awards to retirement-eligible employees since these awards vest on an accelerated basis.