Debt (Tables)

6 Months Ended

Jun. 30, 2015

Debt Disclosure [Abstract]

Contingent Interest on Debt [Table Text Block]

The Trust PIERS have accrued and paid contingent interest (ranging from $0.07 to $0.15 per $50 stated liquidation amount of Trust PIERS) for each quarterly interest period since June 2013. 

Fair Value, by Balance Sheet Grouping [Table Text Block]

The fair value of the Company’s fixed rate debt instruments is based on quoted market prices (Level II) and is summarized as follows (in thousands):

Fair Value of Financial Instruments
	June 30, 2015				December 31, 2014
Financial Instrument	Book Value		Market Value		Book Value		Market Value
4.75% senior notes, due 2022	$	400,000	$	426,000	$	400,000	$	408,000
5.00% senior notes, due 2024	300,000		324,000		300,000		316,700
3.75% convertible senior subordinated notes, due 2025
Carrying value	54,886				54,148		—
Unamortized debt discount	25,080				25,824		—
Principal amount	79,966		282,900		79,972		211,900
4.00% junior subordinated convertible debentures, due 2033
Carrying value	188,883				188,550		—
Unamortized debt discount	116,015				118,133		—
Principal amount	304,898		704,300		306,683		550,200
3.25% convertible senior debentures, due 2035
Carrying value	182,094				178,284		—
Unamortized debt discount	3,939				7,749		—
Principal amount	186,033		228,900		186,033		197,000
3.25% convertible senior exchange debentures, due 2035
Carrying value	218,504		—		216,738		—
Unamortized debt discount	22,963		—		24,729		—
Principal amount	241,467		300,500		241,467		279,500
3.50% convertible senior subordinated notes, due 2044
Carrying value	219,443				218,474		—
Unamortized debt discount	204,807				205,776		—
Principal amount	424,250		599,500		424,250		507,000

Summary of Debt

(in thousands):

	June 30, 2015			December 31, 2014
Revolving loans	$	—		$	—
Senior term loan, due 2019	385,000			395,000
4.75% senior notes, due 2022	400,000			400,000
5.00% senior notes, due 2024	300,000			300,000
3.75% convertible senior subordinated notes, due 2025	79,966			79,972
3.50% convertible senior subordinated notes, due 2044	424,250			424,250
4.00% junior subordinated convertible debentures, due 2033	304,898			306,683
3.25% convertible senior debentures, due 2035	186,033			186,033
3.25% convertible senior exchange debentures, due 2035	241,467			241,467
Capitalized lease and other debt obligations	9,796			13,083
Subtotal	2,331,410			2,346,488
(Subtract) unamortized debt discount	(372,804		)	(382,212		)
(Subtract) current portion of debt	(451,184		)	(446,717		)
Total long-term debt, net	$	1,507,422		$	1,517,559

Convertible debt and related equity

Information relating to the Company’s convertible securities at June 30, 2015 is in the following table:

Convertible Debt	Carrying Value of Equity Component (in thousands)		Remaining Amortization Period	Effective Interest Rate
3.75% convertible senior subordinated notes, due 2025	$	6,913	10.50	8.25	%
4.00% junior subordinated convertible debentures, due 2033	$	117,659	18.00	8.01	%
3.25% convertible senior debentures, due 2035	$	233,901	0.50	7.63	%
3.25% convertible senior exchange debentures, due 2035	$	25,259	5.75	5.24	%
3.50% convertible senior subordinated notes, due 2044	$	208,200	28.65	7.70	%