Accounts payable and accrued expenses (Components of accounts payable and accrued expenses) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Payables and Accruals [Abstract]
Outstanding checks in excess of cash	$ 25,480	$ 17,590
Accounts payable, trade	387,871	372,616
Accrued expenses	180,039	154,560
Product warranties	32,930	30,144
Accrued interest	26,843	34,235
Deferred tax liability	6,309	8,760
Accrued Income Taxes, Current	2,074	0
Accrued compensation and benefits	111,890	97,186
Total accounts payable and accrued expenses	$ 773,436	$ 715,091