Benefit Plans - Stock Options Activity (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Shares, Outstanding at beginning of year	2,860,081	3,000,406	3,511,173
Shares, Assumed in acquisition		356,490
Shares, Exercised		(1,019)
Shares, Forfeited or expired	(537,488)	(495,796)	(510,767)
Shares, Outstanding at end of year	2,322,593	2,860,081	3,000,406
Shares, Exercisable at year-end	2,320,696	2,756,007	2,737,814
Weighted Average Exercise Price, Outstanding at beginning of year	$ 17	$ 17	$ 18
Weighted Average Exercise Price, Assumed in acquisition		$ 17
Weighted Average Exercise Price, Exercised		$ 12
Weighted Average Exercise Price, Forfeited or expired	$ 19	$ 16	$ 14
Weighted Average Exercise Price, Outstanding at end of year	$ 17	$ 17	$ 17
Weighted Average Exercise Price, Exercisable at year-end	$ 17	$ 18	$ 18