Basis of Presentation - Additional Information (Detail) - Subsequent Event	1 Months Ended
	Oct. 18, 2017 $ / shares
Class of Stock [Line Items]
Common stock, dividends per share declared, subsequent event	$ 0.21
Dividends Payable, Date Declared	Oct. 18, 2017
Dividends Payable, Date to be Paid	Dec. 22, 2017
Dividends Payable, Date of Record	Dec. 01, 2017