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Long-Term Debt - Summary of Interest Received and Paid under Term of Cash Flow Swap (Parenthetical) (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 USD ($)
Derivatives, Fair Value [Line Items] |
One-month LIBOR rate | 1.564%
Receive Rate | one-month LIBOR
Cash Flow Swap 2 [Member] |
Derivatives, Fair Value [Line Items] |
Receive Rate | one-month LIBOR
Swap agreement effective date | Jul. 02, 2018
Cash Flow Swap 3 [Member] |
Derivatives, Fair Value [Line Items] |
Receive Rate | one-month LIBOR
Swap agreement effective date | Jul. 02, 2018
Cash Flow Swap 5 [Member] |
Derivatives, Fair Value [Line Items] |
Receive Rate | one-month LIBOR
Swap agreement effective date | Jul. 02, 2018
Cash Flow Swap 4 [Member] |
Derivatives, Fair Value [Line Items] |
Receive Rate | one-month LIBOR
Swap agreement effective date | Jul. 01, 2019
Cash Flow Swap 6 [Member] |
Derivatives, Fair Value [Line Items] |
Receive Rate | one-month LIBOR
Swap agreement effective date | Jul. 01, 2019
Cash Flow Swap 8 [Member] |
Derivatives, Fair Value [Line Items] |
Receive Rate | one-month LIBOR
Derivative notional amount interest rate caps, remainder of fiscal year | $ 62,500
Derivative notional amount interest rate caps, second year | 93,750
Derivative notional amount interest rate caps, third year | 78,125
Derivative notional amount interest rate caps, fourth year | 37,500
Payment of interest rate | $ 0
Cash Flow Swap 9 [Member] |
Derivatives, Fair Value [Line Items] |
Receive Rate | one-month LIBOR
Derivative notional amount interest rate caps, remainder of fiscal year | $ 62,500
Derivative notional amount interest rate caps, second year | 93,750
Derivative notional amount interest rate caps, third year | 78,125
Derivative notional amount interest rate caps, fourth year | 37,500
Payment of interest rate | $ 0
Cash Flow Swap 10 [Member] |
Derivatives, Fair Value [Line Items] |
Receive Rate | one-month LIBOR
Derivative notional amount interest rate caps, remainder of fiscal year | $ 62,500
Derivative notional amount interest rate caps, second year | 93,750
Derivative notional amount interest rate caps, third year | 78,125
Derivative notional amount interest rate caps, fourth year | 37,500
Payment of interest rate | $ 0
Cash Flow Swap 11 [Member] |
Derivatives, Fair Value [Line Items] |
Receive Rate | one-month LIBOR
Derivative notional amount interest rate caps, remainder of fiscal year | $ 62,500
Derivative notional amount interest rate caps, second year | 93,750
Derivative notional amount interest rate caps, third year | 78,125
Derivative notional amount interest rate caps, fourth year | 37,500
Payment of interest rate | $ 0

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