Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Operating activities:
Net income	$ 26,491,000	$ 13,109,000
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation	7,404,000	3,792,000
Depreciation and amortization	4,044,000	3,249,000
Fair value adjustment to contingent acquisition consideration	0	15,000
Deferred income taxes	1,343,000	(8,539,000)
Deferred income taxes related to the Tax Act	12,610,000	0
Changes in operating assets and liabilities:
Increase in restricted cash	(2,982,000)	(4,032,000)
Increase in accounts receivable, prepaid expenses and other assets	(877,000)	(1,088,000)
Increase in advanced commissions	(2,548,000)	(12,470,000)
Decrease in income taxes receivable	0	591,000
(Decrease) increase in income taxes payable	(1,334,000)	2,121,000
Increase in accounts payable, accrued expenses and other liabilities	9,884,000	11,960,000
Increase in deferred revenue	232,000	46,000
(Decrease) increase in due to member pursuant to tax receivable agreement	(531,000)	9,233,000
Decrease in due to member related to the Tax Act	(11,835,000)	0
Net cash provided by operating activities	41,901,000	17,987,000
Investing activities:
Capitalized internal-use software and website development costs	(2,956,000)	(3,052,000)
Purchases of property and equipment	(509,000)	(61,000)
Net cash used in investing activities	(3,465,000)	(3,113,000)
Financing activities:
Proceeds from borrowings under revolving line of credit	0	7,500,000
Payments on borrowings under revolving line of credit	0	(15,000,000)
Payments for contingent acquisition consideration	0	(547,000)
Payments for noncompete obligation	(96,000)	(192,000)
Class A common stock withheld in treasury from restricted share vesting	(842,000)	(160,000)
Issuances of Class A common stock under equity compensation plans	33,000	19,000
Issuances of Class A common stock from treasury	0	21,000
Purchases of Cass A common stock pursuant to share repurchase plan	(4,923,000)	0
Distributions to member	(5,477,000)	(1,996,000)
Net cash used in financing activities	(11,305,000)	(10,355,000)
Net increase in cash and cash equivalents	27,131,000	4,519,000
Cash and cash equivalents at beginning of period	12,214,000	7,695,000
Cash and cash equivalents at end of period	39,345,000	12,214,000
Supplemental disclosure of non-cash financing activities:
Change in due to member related to Exchange Agreement	18,618,000	0
Change in deferred tax asset related to Exchange Agreement	(20,732,000)	0
Issuance of Class A common stock in a private offering related to Exchange Agreement	16,487,000	0
Exchange of Class B membership interests related to Exchange Agreement	(14,374,000)	0
Declared but unpaid distribution to member of Health Plan Intermediaries Holdings, LLC	$ 638,000	$ 2,761,000