Other Comprehensive Loss as Component of Net Periodic Benefit Cost (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Domestic Plan
Pension cost in accumulated other comprehensive loss:
Net actuarial loss	$ (85,984)	$ (76,038)
TCN Plan
Pension cost in accumulated other comprehensive loss:
Net actuarial loss	(6,738)	(4,525)
Recognized in 2012 | Domestic Plan
Pension cost in accumulated other comprehensive loss:
Net actuarial loss	9,725
Recognized in 2012 | TCN Plan
Pension cost in accumulated other comprehensive loss:
Net actuarial loss	1,785
To Be Recognized in 2013 | Domestic Plan
Pension cost in accumulated other comprehensive loss:
Net actuarial loss	11,820
To Be Recognized in 2013 | TCN Plan
Pension cost in accumulated other comprehensive loss:
Net actuarial loss	$ 2,029