Share-Based Payment Arrangements - Schedule of Option Activity Under Stock Option Plans (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of Shares, Outstanding at Beginning | shares	939,393
Number of Shares, Exercised | shares	(11,577)
Number of Shares, Cancelled/Forfeited | shares	(70,586)
Number of Shares, Expired | shares	(111,424)
Number of Shares, Outstanding at Ending | shares	745,806
Number of Shares, Exercisable at Ending | shares	675,880
Weighted- Average Exercise Price, Outstanding at Beginning | $ / shares	$ 37.21
Weighted- Average Exercise Price, Exercised | $ / shares	29.94
Weighted- Average Exercise Price, Cancelled/Forfeited | $ / shares	36.15
Weighted- Average Exercise Price, Expired | $ / shares	34.79
Weighted- Average Exercise Price, Outstanding at Ending | $ / shares	37.55
Weighted- Average Exercise Price, Exercisable at Ending | $ / shares	$ 38.35
Weighted-Average Remaining Contractual Term, Outstanding at Ending Balance (in years)	3 years 7 months 6 days
Weighted-Average Remaining Contractual Term, Exercisable at Ending Balance (in years)	3 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding at Ending | $	$ 0
Aggregate Intrinsic Value, Exercisable at Ending | $	$ 0