Schedule II Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 17,203	$ 17,005	$ 18,757
Acquired by Purchase or Merger	1,201	0	56
Charged to Cost and Expense	4,730	5,869	3,810
Reductions	(3,524)	(5,427)	(5,138)
Other	(716)	(244)	(480)
Balance at End of Year	18,894	17,203	17,005
Valuation Allowance of Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	14,063	17,275	20,396
Acquired by Purchase or Merger	0	0	0
Additions	133,431	0	0
Reductions	(6,242)	(3,212)	(3,121)
Other	0	0	0
Balance at End of Year	141,252	14,063	17,275
LIFO Reserve [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	50,705	53,374	53,327
Acquired by Purchase or Merger	0	0	0
Charged to Cost and Expense	4,166	0	47
Reductions	(4,102)	(2,669)	0
Other	0	0	0
Balance at End of Year	$ 50,769	$ 50,705	$ 53,374