Derivative Instruments and Hedging Activities - Commitment of Foreign Currency Forward Contracts (Detail) - Jun. 30, 2016 - Foreign currency forward contracts [Member]
€ in Thousands, SGD in Thousands, NOK in Thousands, $ in Thousands

USD ($)

€ / $

NOK / $

SGD / $

EUR (€)

€ / $

NOK / $

SGD / $

NOK

€ / $

NOK / $

SGD / $

SGD

€ / $

NOK / $

SGD / $

Derivative [Line Items]

Fair Value / Carrying Amount of Asset (Liability)

$ (3,762)

Expected Maturity Amount of Foreign Currency Derivatives in Current Year

66,629

Expected Maturity Amount of Foreign Currency Derivatives in Next Fiscal Year

$ 47,947

Euro [Member]

Derivative [Line Items]

Contract Amount in Foreign Currency | €

€ 4,500

Average Forward Rate | € / $

0.92

Fair Value / Carrying Amount of Asset (Liability)

$ 124

Expected Maturity Amount of Foreign Currency Derivatives in Current Year

4,886

Expected Maturity Amount of Foreign Currency Derivatives in Next Fiscal Year

$ 0

Norwegian Kroner [Member]

Derivative [Line Items]

Contract Amount in Foreign Currency | NOK

NOK 762,500

Average Forward Rate | NOK / $

8.02

Fair Value / Carrying Amount of Asset (Liability)

$ (3,869)

Expected Maturity Amount of Foreign Currency Derivatives in Current Year

47,151

Expected Maturity Amount of Foreign Currency Derivatives in Next Fiscal Year

$ 47,947

Singapore Dollar [Member]

Derivative [Line Items]

Contract Amount in Foreign Currency | SGD

SGD 19,637

Average Forward Rate | SGD / $

1.35

Fair Value / Carrying Amount of Asset (Liability)

$ (17)

Expected Maturity Amount of Foreign Currency Derivatives in Current Year

14,592

Expected Maturity Amount of Foreign Currency Derivatives in Next Fiscal Year

$ 0