Stock Incentive Plans and Stock Purchase Plans	3 Months Ended
Stock Incentive Plans and Stock Purchase Plans	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Incentive Plans and Stock Purchase Plans	8. Stock Incentive Plans and Stock Purchase Plans: The Company’s Amended and Restated 2008 Incentive Compensation Plan, as amended (the “Amended and Restated 2008 Incentive Plan”) provides for grants of stock options, stock appreciation rights, restricted stock, deferred stock, and other stock-related awards and performance awards that may be settled in cash, stock or other property. Under the Amended and Restated 2008 Incentive Plan, options to purchase shares of common stock may be granted at a price not less than the fair market value of the shares on the date of grant. The options must be exercised within 10 years from the date of grant and generally become exercisable on a pro rata basis over a three-year period from the date of grant. The Company issues new shares of its common stock upon exercise of its stock options. Restricted stock awards generally vest over periods of three years upon the fulfillment of specified service-based conditions and in certain instances performance-based conditions. The Company recognizes compensation expense related to its restricted stock awards ratably over the corresponding vesting periods. At March 31, 2017, the Company had 4.5 million shares available for future grants and awards under its Amended and Restated 2008 Incentive Plan. Under the Company’s 1996 Non-Qualified Employee Stock Purchase Plan, as amended (the “ESPP”), employees are permitted to purchase the Company’s common stock at 85% of market value on January 1st, April 1st, July 1st and October 1st of each year. Under the Company’s 2015 Non-Qualified Stock Purchase Plan (the “SPP”), certain eligible non-employee service providers are permitted to purchase the Company’s common stock at 90% of market value on January 1st, April 1st, July 1st and October 1st of each year. Each of the ESPP and the SPP provide for the issuance of an aggregate of 2.6 million shares of the Company’s common stock less the number of shares of common stock purchased under the other plan. In accordance with the provisions of the accounting guidance for stock-based compensation, the Company recognizes stock-based compensation expense for the discount received by participating employees and non-employee service providers. During the three months ended March 31, 2017, 66,675 shares were issued under the ESPP and SPP. At March 31, 2017, the Company had approximately 2.2 million shares in aggregate reserved for issuance under the ESPP and SPP. During the three months ended March 31, 2017 and 2016, the Company recognized $7.5 million and $8.9 million, respectively, of stock-based compensation expense.

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.