Annual report pursuant to Section 13 and 15(d)

Long-Term Debt - Summary of Interest Received and Paid under Term of Cash Flow Swap (Parenthetical) (Detail)

v2.4.1.9
Long-Term Debt - Summary of Interest Received and Paid under Term of Cash Flow Swap (Parenthetical) (Detail)
12 Months Ended
Dec. 31, 2014
Derivatives, Fair Value [Line Items]  
One-month LIBOR rate 0.17%us-gaap_DerivativeVariableInterestRate
Receive Rate One-month LIBOR
Swap agreement effective date Jul. 01, 2015
Cash Flow Swap 11 [Member]  
Derivatives, Fair Value [Line Items]  
Receive Rate one-month LIBOR
Swap agreement effective date Jul. 01, 2016
Cash Flow Swap 12 [Member]  
Derivatives, Fair Value [Line Items]  
Receive Rate one-month LIBOR
Swap agreement effective date Jul. 03, 2017