Pension Plans and Postretirement Benefits - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets		6.50%	5.30%
Domestic Plan
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	6.50%	5.75%	7.05%
Expected rate of return on plan assets	6.50%
Employer contributions, percentage match of participants' contributions	50.00%
Employer contributions, percentage unmatch of participants' contributions	3.00%
Defined contribution plans costs	$ 6.8	$ 6.6	$ 6.7
Domestic Plan | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan matching percent of compensation	6.00%
TCN Plan
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	6.90%	5.75%	7.50%
Expected rate of return on plan assets	6.90%
Employer contributions, percentage match of participants' contributions	50.00%
Employer contributions, percentage unmatch of participants' contributions	3.00%
Defined contribution plans costs	$ 1.6
TCN Plan | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan matching percent of compensation	6.00%