Common Stock and Subsequent Event Shareholder Rights Plan (Details)	Aug. 26, 2017 $ / shares shares	Aug. 25, 2017 right shares	Feb. 25, 2017 shares	Aug. 27, 2016 shares
Class of Warrant or Right [Line Items]
Preferred stock, Shares authorized	1,000,000		1,000,000	1,000,000
Rights Plan
Class of Warrant or Right [Line Items]
Preferred stock purchase right issued per common stock share outstanding | right		1
Class of warrant or right, number of securities called by each right	0.0001
Class of warrant or right, exercise price of rights (in usd per share) | $ / shares	$ 26.00
Class of warrant or right, percentage common stock ownership trigger threshold	12.50%
Preferred Class A | Rights Plan
Class of Warrant or Right [Line Items]
Preferred stock, Shares authorized		10,000
Board of Directors | Rights Plan
Class of Warrant or Right [Line Items]
Class of warrant or right, number of securities called by each right	0.0001