Quarterly report pursuant to Section 13 or 15(d)

Debt (Narrative) (Details)

v2.4.0.8
Debt (Narrative) (Details) (USD $)
2 Months Ended 9 Months Ended 1 Months Ended
Jun. 30, 2013
Sep. 30, 2013
Dec. 31, 2012
Nov. 30, 2012
5.75% Senior Notes [Member]
May 31, 2011
5.75% Senior Notes [Member]
Debt Instrument [Line Items]          
Senior notes, at par   $ 425,000,000 $ 425,000,000 $ 175,000,000 $ 250,000,000
Interest rate on notes, percentage       5.75% 5.75%
Senior notes due date       Jun. 01, 2017 Jun. 01, 2017
Senior notes, effective yield       4.29% 6.00%
Debt Instrument, Unamortized Premium   6,495,000 7,823,000    
Interest rate swap fair value   10,596,000 16,304,000    
Variable rate of swap, percentage   3.76%      
Revolving credit facility, maximum borrowing capacity   500,000,000      
Line of Credit Facility, Amount Outstanding   0      
Line of Credit Facility, Covenant Terms The agreement contains non-financial and financial covenants, including requirements of minimum fixed charge coverage ratios, maximum debt-to-EBITDA ratios and minimum tangible net worth. The Company is required not to exceed a maximum debt-to-EBITDA ratio of 3.25 as of September 30, 2013 and 3.0 as of December 31, 2013 and thereafter.        
Line of Credit Facility, Current Borrowing Capacity   400,000,000      
Mortgage Loans on Real Estate     0    
Revolving credit facility, due date   Jun. 01, 2018      
Compensating Balance, Amount   0      
Revolving credit agreement   0 0    
Letters of credit outstanding amount   $ 28,682,000      
Letters of credit bore interest   0.52%