Share-Based Payment Arrangements - Schedule of Option Activity Under Stock Option Plans (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of Shares, Outstanding at Beginning	933,750
Number of Shares, Exercised	0
Number of Shares, Cancelled/Forfeited	(11,473)
Number of Shares, Expired	(75,480)
Number of Shares, Outstanding at Ending	846,797
Number of Shares, Exercisable at Ending	691,344
Weighted- Average Exercise Price, Outstanding at Beginning	$ 37.03
Weighted- Average Exercise Price, Exercised	$ 0
Weighted- Average Exercise Price, Cancelled/Forfeited	$ 36.79
Weighted- Average Exercise Price, Expired	$ 31.20
Weighted- Average Exercise Price, Outstanding at Ending	$ 37.55
Weighted- Average Exercise Price, Exercisable at Ending	$ 39.20
Weighted-Average Remaining Contractual Term, Outstanding at Ending Balance (in years)	4 years 4 months 24 days
Weighted-Average Remaining Contractual Term, Exercisable at Ending Balance (in years)	3 years 9 months 18 days
Aggregate Intrinsic Value, Outstanding at Ending	$ 15
Aggregate Intrinsic Value, Exercisable at Ending	$ 6