XML 55 R65.htm IDEA: XBRL DOCUMENT

Employee Benefits - Pension Plan - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Pension expense	$ 0.2	$ 1.0	$ 3.1	$ 3.2
PWAC Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension expense	0.2	0.2	0.5	0.5
Accrued liability for the unfunded liability	$ 9.6		$ 9.6		$ 10.5

The amount of pension benefit costs recognized during the period for (1) defined benefit plans and (2) defined contribution plans. For defined benefit plans, pension expense includes the following components: service cost, interest cost, expected return on plan assets, gain (loss) on plan assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. For defined contribution plans, the pension expense generally equals the firm's contribution to employees' accounts (if the firm contributes) during the period.

+ References+ Details