Cash Collateral Pledged	12 Months Ended
Cash Collateral Pledged	Dec. 31, 2016
Cash and Cash Equivalents [Abstract]
Cash Collateral Pledged	Cash Collateral Pledged As of December 31, 2016 and 2015, the Company pledged cash collateral in the amount of $7.8 million and $10.1 million, respectively, which relates to letters of credit issued to the landlords of the Company's premises in New York City, Boston, Stamford and San Francisco. The Company also has a letter of credit, in the amount of $5.5 million, due March 2017, for which cash is pledged as collateral under a reinsurance agreement. (See Note 19).

The entire disclosure for cash and cash equivalent footnotes, which may include the types of deposits and money market instruments, applicable carrying amounts, restricted amounts and compensating balance arrangements. Cash and equivalents include: (1) currency on hand (2) demand deposits with banks or financial institutions (3) other kinds of accounts that have the general characteristics of demand deposits (4) short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments maturing within three months from the date of acquisition qualify.