Fair Value and Credit Risk of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2014

Fair Value Disclosures [Abstract]

Fair Value Measurement of Financial Assets

The following table sets forth information regarding the recurring fair value measurement of our financial assets as reflected on our Consolidated Balance Sheet as of December 31, 2014:

			Fair Value Measurements at Reporting Date Using
Description	As of December 31, 2014		(Level 1) Quoted Prices in Active Markets for Identical Assets		(Level 2) Significant Other Observable Inputs		(Level 3) Significant Unobservable Inputs
Cash equivalents:
Money market fund	$	60,960	$	60,960	$	0	$	0
Restricted cash:
Money market fund		1,967		1,967		0		0
Collateral deposits:
Money market fund		8,628		8,628		0		0
	$	71,555	$	71,555	$	0	$	0

The following table sets forth information regarding the recurring fair value measurement of our financial assets as reflected on our Consolidated Balance Sheet as of December 31, 2013:

			Fair Value Measurements at Reporting Date Using
Description	As of December 31, 2013		(Level 1) Quoted Prices in Active Markets for Identical Assets		(Level 2) Significant Other Observable Inputs		(Level 3) Significant Unobservable Inputs
Cash equivalents:
Money market fund	$	214,985	$	214,985	$	0	$	0
Restricted cash:
Money market fund		2,433		2,433		0		0
Collateral deposits:
Money market fund		8,626		8,626		0		0
	$	226,044	$	226,044	$	0	$	0