Long-Term Debt (Tables)

6 Months Ended

Jun. 30, 2013

Long-Term Debt [Abstract]

Financial Debt Covenants

Description	Requirement
Leverage Ratio (Consolidated Indebtedness/Consolidated  Adj. EBITDA)	<  3.50 to 1.00
Fixed Charge Coverage Ratio (Consolidated Free Cash Flow/Consolidated Fixed Charges)	>  1.50 to 1.00
Annual Operating Lease Commitment	< $30.0 million

Debt Amounts Included In Consolidated Balance Sheet

	June 30, 2013		December 31, 2012
Principal amount of convertible debentures	$	186,956	$	186,956
Unamortized debt discount		(7,802)		(12,066)
Carrying amount of convertible debentures	$	179,154	$	174,890
Additional paid in capital (net of tax)	$	31,310	$	31,310

Interest Expense Included In Consolidated Income Statement

	Three months ended June 30,				Six months ended June 30,
	2013		2012		2013		2012
Cash interest expense	$	1,230	$	1,350	$	2,430	$	2,683
Non-cash amortization of debt discount		2,150		2,009		4,264		3,985
Amortization and write-off of debt costs		317		313		1,097		621
Total interest expense	$	3,697	$	3,672	$	7,791	$	7,289