Long-Term Debt - 2011 Senior Credit Facility (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Nov. 15, 2013	Nov. 16, 2012	Aug. 22, 2012	May 11, 2011	Nov. 14, 2012
Debt Instrument [Line Items]
Payments of financing costs	$ 0	$ 763,000	$ 125,000
Principal payments to non-consenting Term Loan Facility lenders	0	0	13,796,000
Repayments of senior debt	0	0	36,007,000
Rate less than percent difference between debt instruments	10.00%
Loss on extinguishment of debt	(493,000)	(750,000)	(1,010,000)
Long-term debt, gross				325,000,000
Line of Credit [Member] | 2011 Senior Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity							350,000
Percent of amendment fee paid to consenting lenders					0.50%
Payments of financing costs					125,000		8,065,000
Principal payments to non-consenting Term Loan Facility lenders						13,796,000
Total cash paid in connection with early repayment of debt				316,617,000
Loss on extinguishment of debt				750,000		(464,000)
Debt discount related to an amendment fee paid to consenting lenders					639,000
Amendment fee percentage					0.25%
Interest expense related to bank, legal and accounting related fees paid to third parties to execute the Amendment					1,569,000
Early repayment of senior debt				315,743,000
Interest paid				807,000
Letter of credit and commitment fees				67,000
Senior Notes [Member] | Senior Discount Notes [Member]
Debt Instrument [Line Items]
Debt stated interest rate	11.00%
Secured Debt [Member] | 2011 Senior Credit Facility [Member]
Debt Instrument [Line Items]
Debt unamortized discount					300,000
Long-term debt, gross					60,000
Secured Debt [Member] | 2011 Term Loan Facility [Member]
Debt Instrument [Line Items]
Debt Amendment, Decrease in Interest Rate						1.25%
Line of credit maximum borrowing capacity							300,000
Debt Instrument, Discount Percentage							1.00%
Percent of amendment fee paid to consenting lenders							1.00%	1.00%
Debt unamortized discount							3,000,000
Repayments of senior debt						15,000,000
Loss on extinguishment of debt			546,000
Write-off of unamortized debt issuance cost			269,000			260,000
Write-off of unamortized original issue discount			277,000			204,000
Debt discount related to an amendment fee paid to consenting lenders						2,707,000
Amendment fee percentage						1.00%
Interest expense related to bank, legal and accounting related fees paid to third parties to execute the Amendment						1,390,000
Revolving Credit Facility [Member] | 2011 Revolving Loan Facility [Member]
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity							$ 50,000