Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Additional Information (Detail)

v2.4.0.8
Fair Value Measurements - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2014
Dec. 31, 2013
Mar. 31, 2014
Minimum [Member]
Mar. 31, 2014
Maximum [Member]
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items]        
Discount rates based on market observations     7.00% 15.00%
Discount rates to determine fair market value of underlying assets     8.00% 10.00%
Cash deposits held in U.S. banks $ 82.6 $ 81.7    
Bank deposits $ 81.0 $ 80.3