Stock-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Number of Shares
Number of shares, beginning balance		105,100
Number of shares, forfeited or expired		5,325
Number of shares, ending balance		99,775.000	105,100
Weighted Average Exercise Price
Weighted average exercise price, beginning balance		$ 52.96
Weighted average exercise price, forfeited or expired		$ 30.30
Weighted average exercise price, ending balance		$ 54.15	$ 52.96
Additional Disclosures
Weighted average remaining contractual life (years), beginning balance		2 years 10 months 24 days	3 years 8 months 12 days
Weighted average remaining contractual life (years), ending balance		2 years 10 months 24 days	3 years 8 months 12 days
Weighted average remaining contractual life (years), vested or expected to vest		2 years 10 months 24 days
Weighted average remaining contractual life (years), exercisable		2 years 10 months 24 days
Number of shares, vested or expected to vest		99,775
Number of shares, exercisable		99,775
Weighted average exercise price, vested or expected to vest		$ 54.15
Weighted average exercise price, exercisable		$ 54.15
Number of Units
Number of units, beginning balance		11,387,000
Number of units, granted		11,898,000
Number of units, vested		23,285,000	100,000
Number of units, ending balance		0	11,387,000
Weighted Average Grant Date Fair Value
Weighted average grant date fair value, beginning balance		$ 21,520.00
Weighted average grant date fair value, granted		$ 20.49	$ 16.30	$ 28.01
Weighted average grant date fair value, vested		$ 21,520.00
Weighted average grant date fair value, ending balance		$ 0.00	$ 21,520.00
Non vested shares restricted shares, vesting period			4 years
Shares available for future issuance		1,500,000
Accelerated vesting of restricted shares	300,000
Accelerated stock compensation expense	$ 6,200,000
Intrinsic value of options exercised				100,000
Stock option exercised		0	0	4,000
Proceeds from exercise of stock options		0	0	100,000
Tax benefit from stock options exercised				0
Fair values of vested restricted stock and stock options		$ 500,000	$ 1,500,000	$ 9,700,000
Market Condition Restricted Stock Units
Number of Units
Number of units, granted				23,192
Weighted Average Grant Date Fair Value
Weighted average grant date fair value, granted				$ 15.69
Performance period (in years)			3 years