Fair Values - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Assets
Derivatives	$ 625	$ 8,657
Other assets	11,826	14,220
Liabilities
Derivatives	9,289	1,448
Level 2 [Member]
Assets
Derivatives	625	8,657
Other assets	1,605	1,659
Liabilities
Derivatives	9,289	1,448
Level 3 [Member]
Assets
Other assets	$ 10,221	$ 12,561