Long-Term Debt Long-Term Debt (Minimum Required Interest Coverage Ratio) (Details) (Minimum [Member], Subsequent Event [Member], Combined Credit Agreements [Member])	3 Months Ended
	Mar. 31, 2013
Q2 2013 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.25
Q3 2013 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.25
Q4 2013 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.25
Q1 2014 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.20
Q2 2014 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.15
Q3 2014 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.10
Q4 2014 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.10
Q1 2015 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.10
Q2 2015 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.15
Q3 2015 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.15
Q4 2015 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.20
Q1 2016 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.50
Q2 2016 [Member]
Debt Instrument [Line Items]
Interest coverage ratio	2.0