Equity (tMEDS) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended		12 Months Ended
	May 04, 2010		Dec. 31, 2012
Class of Stock [Line Items]
Units issued	13,800,000	[1]
Unit price	$ 25.00
Gross proceeds	$ 345,000
Issuance costs	11,423
Net proceeds	333,577
Other Assets (Prepaid Issuance Costs) [Member]
Class of Stock [Line Items]
Impact on Consolidated Balance Sheet	2,342
Long-term Debt [Member]
Class of Stock [Line Items]
Impact on Consolidated Balance Sheet	70,355
Additional Paid-In Capital [Member]
Class of Stock [Line Items]
Impact on Consolidated Balance Sheet	265,564
Equity Component [Member]
Class of Stock [Line Items]
Units issued	13,800,000	[1]
Unit price	$ 19.901803
Gross proceeds	274,645
Issuance costs	9,081
Net proceeds	265,564
Fair value weighted-average assumptions - risk-free interest rate			1.77%
Fair value weighted-average assumptions - expected stock price volatility			60.00%
Fair value weighted-average assumptions - dividend yield			1.45%
Fair value weighted-average assumptions - term (years)			3 years 0 months 11 days
Reclassification from additional paid-in capital to common stock, value per common share issued			$ 1.00
Number of tMEDs settled to date (units)			286,600
Number of common stock shares issued to date (shares)			2,171,222
Equity Component [Member] | Less than or Equal to $2.75 [Member]
Class of Stock [Line Items]
Settlement rate (per unit)			9.0909
Settlement, applicable market value of common stock, maximum (per share)			$ 2.75
Equity Component [Member] | Between $2.75 and $3.30 [Member]
Class of Stock [Line Items]
Settlement, applicable market value of common stock, minimum (per share)			$ 2.75
Settlement, applicable market value of common stock, maximum (per share)			$ 3.30
Settlement rate basis, number of shares equivalent value			$ 25
Equity Component [Member] | Greater than or Equal to $3.30 [Member]
Class of Stock [Line Items]
Settlement rate (per unit)			7.5758
Settlement, applicable market value of common stock, maximum (per share)			$ 3.30
Equity Component [Member] | Other Assets (Prepaid Issuance Costs) [Member]
Class of Stock [Line Items]
Impact on Consolidated Balance Sheet	0
Equity Component [Member] | Long-term Debt [Member]
Class of Stock [Line Items]
Impact on Consolidated Balance Sheet	0
Equity Component [Member] | Additional Paid-In Capital [Member]
Class of Stock [Line Items]
Impact on Consolidated Balance Sheet	265,564
Debt Component [Member]
Class of Stock [Line Items]
Units issued	13,800,000	[1]
Unit price	$ 5.098197
Gross proceeds	70,355
Issuance costs	2,342
Net proceeds	68,013
Fair value assumptions - quarterly cash payments			2.0625%
Fair value assumptions - maturity date			May 15, 2013
Fair value assumptions - assumed discount rate			10.00%
Debt Component [Member] | 13.00% Junior Subordinated Amortizing Notes with Quarterly Interest and Principal Payments through May 15, 2013 [Member]
Class of Stock [Line Items]
Initial principal amount per unit			$ 5.098197
Interest rate per annum			13.00%
Quarterly interest and principal payment per unit			$ 0.515625
Debt Component [Member] | Other Assets (Prepaid Issuance Costs) [Member]
Class of Stock [Line Items]
Impact on Consolidated Balance Sheet	2,342
Debt Component [Member] | Long-term Debt [Member]
Class of Stock [Line Items]
Impact on Consolidated Balance Sheet	70,355
Debt Component [Member] | Additional Paid-In Capital [Member]
Class of Stock [Line Items]
Impact on Consolidated Balance Sheet	$ 0

[1] There are two components of each tMEDS unit; therefore, there are 13.8 million units of the equity component, 13.8 million units of the debt component, and 13.8 million units of tMEDS, which includes both the debt and equity components.