Other Long-Term Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Restricted Cash and Cash Equivalents Items [Line Items]
Cash surrender value of corporate-owned life insurance policies	$ 3,723	$ 3,240
Prepaid commissions	6,556	5,302
Restricted cash	3,326	3,317
Prepaid expenses, deposits and other	2,929	2,058
Total other long-term assets	16,534	13,917
Funds deposited in escrow	1,800	1,800
Cash Receipts Held In Escrow
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	2,700	2,700
Restricted Cash For Performance Guarantee
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 600	$ 600