Consolidated Valuation And Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Accounts Receivable - Allowance For Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 4,960		$ 4,954		$ 4,952
Provision charged to expense	(471)		245		424
Reserve adjustments	(394)		(136)		(401)
Write-offs, net of recoveries	(637)		(103)		(21)
Balance at end of period	3,458		4,960		4,954
Finance Receivables - Allowance For Credit Losses [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	110,693		107,667		125,449
Provision charged to expense	80,946		60,008		22,239
Write-offs, net of recoveries	(64,275)		(56,982)		(40,021)
Balance at end of period	127,364		110,693		107,667
Inventories - Allowance For Obsolescence [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	17,463	[1]	22,936	[1]	23,204	[1]
Provision charged to expense	19,044	[1]	5,254	[1]	9,489	[1]
Reserve adjustments	(399)	[1]	(1,281)	[1]	(696)	[1]
Write-offs, net of recoveries	(18,333)	[1]	(9,446)	[1]	(9,061)	[1]
Balance at end of period	17,775	[1]	17,463	[1]	22,936	[1]
Deferred Tax Assets - Valuation Allowance [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	21,818		16,314		14,914
Reserve adjustments	3,644		5,504		1,400
Balance at end of period	$ 25,462		$ 21,818		$ 16,314

[1] Inventory obsolescence reserves deducted from cost determined on first-in first-out (FIFO) basis, before deductions for last-in, first-out (LIFO) valuation reserves.