New Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Thousands		1 Months Ended
	Jan. 01, 2018	Feb. 28, 2018
Accounting Standards Update 2016-01 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment	$ 132
Accounting Standards Update 2017-12 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment	$ 13
Accounting Standards Update 2018-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassified stranded tax effects from AOCI to retained earnings		$ 12,900