The Company - Additional Information (Detail) $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2018 USD ($)	May 05, 2018 USD ($)	Aug. 04, 2018 USD ($)	Nov. 03, 2018 USD ($) Gallery Store State Showroom	Feb. 03, 2018 USD ($)
Organization Consolidation and Presentation of Financial Statements [Line Items]
Number of retail Galleries | Gallery				86
Number of outlet stores | Store				37
Number of states | State				32
Number of waterworks showrooms | Showroom				15
Total cost of convertible note hedge transactions				$ 91,857
Cash proceeds from sale of warrants				51,021
Total cash proceeds, net of discounts upon original issuance and offering costs	$ 287,800
Discounts upon original issuance and offering costs	6,300
Overstatement of Treasury Stock [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Revision due to prior year misstatement in current year financial statements, amount		$ 19,500	$ 19,500		$ 19,500
Overstatement of Additional Paid-in Capital [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Revision due to prior year misstatement in current year financial statements, amount		$ 19,500	$ 19,500		$ 19,500
Convertible Senior Notes Due 2023 [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Debt instrument, principal amount				$ 335,000
Cash proceeds from sale of warrants	51,000
Convertible Senior Notes Due 2023 [Member] | Convertible Bond Hedge and Warrant Transactions [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Total cost of convertible note hedge transactions	91,900
Private Placement [Member] | Convertible Senior Notes Due 2023 [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Debt instrument, principal amount	$ 300,000
Debt instrument, interest rate	0.00%
Over Allotment Option in Private Placement [Member] | Convertible Senior Notes Due 2023 [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Debt instrument, principal amount	$ 35,000