Interim Financial Information - Cumulative Effect of the Changes Made and Impact of Applying Topic 606 on the Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Assets
Accounts and notes receivable, net	$ 169,318	$ 200,234	$ 188,611
Inventories, net	1,733,756	1,759,633	1,763,293
Prepaid expenses and other current assets	77,996	50,745	42,062
Liabilities
Accounts payable	428,441	414,737	412,981
Deferred income taxes	137,826	127,897	124,404
Stockholders' equity
Retained earnings	1,368,946	1,257,720	1,246,323
Retained earnings and accumulated other comprehensive loss	1,240,052
Balances Without Adoption of Topic 606
Assets
Accounts and notes receivable, net	156,900		188,611
Inventories, net	1,737,582		1,763,293
Prepaid expenses and other current assets	65,989		42,062
Liabilities
Accounts payable	426,505		412,981
Deferred income taxes	133,453		124,404
Stockholders' equity
Retained earnings			$ 1,246,323
Retained earnings and accumulated other comprehensive loss	1,225,762
Adjustment due to Topic 606 \| ASU 2014-09
Assets
Accounts and notes receivable, net	12,418	11,623
Inventories, net	(3,826)	(3,660)
Prepaid expenses and other current assets	12,007	8,683
Liabilities
Accounts payable	1,936	1,756
Deferred income taxes	4,373	3,493
Stockholders' equity
Retained earnings		$ 11,397
Retained earnings and accumulated other comprehensive loss	$ 14,290

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