Derivative and Hedging Activities - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2018 USD ($) Instruments	Jan. 01, 2018 USD ($)
Accounting Standards Update 2017-12 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Adjustment to retained earnings and accumulated other comprehensive income to reclassify cash flow hedge		$ 100,000
Interest Expense [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from accumulated other comprehensive income to interest expense	$ 500,000
Interest Rate Swap [Member] | Cash Flow Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative instruments	$ 100,000,000
Derivatives, number of instruments held | Instruments	2
Notional amount amortized	$ 95,300,000
Notional amount maturity date	May 31, 2022