Summary of Significant Accounting Policies - Advertising, Cash, and Deferred Lease (Details) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Nov. 30, 2015	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Advertising expense			$ 6,384,000	$ 11,057,000	$ 7,903,000
Captive insurance required balance			250,000
Cash related to captive insurance that was included in cash and cash equivalents		$ 275,000	276,000	275,000
Amortization of lease incentives			3,190,000	2,920,000	2,771,000
Write off of deferred lease liability					2,924,000
Net occupancy gain on club closure					1,442,000
Gain (loss) on lease termination		$ 2,967,000	0	2,967,000	0
Proceeds from termination of lease by landlord	$ 3,090,000
Operating Expense [Member]
Financing Receivable, Impaired [Line Items]
Lease termination penalty			$ 329,000	$ 1,550,000	$ 1,482,000