International Business Machines Corporation Information Technology Outsourcing Agreement - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended	1 Months Ended
	Dec. 31, 2012	Mar. 17, 2008 Outsourcing Agreement
Information Technology Outsourcing Agreement [Line Items]
Initial term of outsourcing agreement with IBM		7 years
Services agreement, termination fee	$ 3.0
Services agreement, effective termination date	Jan. 31, 2013
Transition services completion period		21 months
Transition services cost, recognized	6.7
Payment for transition services cost	6.5
Transition services lability forgiven	$ 0.2