Summary of Significant Accounting Policies - Effect of the Adoption of ASU 2014-09 and 2017-07 (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net sales	$ 1,929,480	$ 1,894,066	$ 1,951,230	$ 1,980,507	$ 1,934,997	$ 1,937,620	$ 1,926,722	$ 1,995,686	$ 7,755,283	$ 7,795,025	$ 7,710,226
Cost of sales									6,100,005	5,976,958	5,722,112
Gross profit	$ 383,394	$ 390,597	$ 432,784	$ 448,503	$ 446,530	$ 441,838	$ 467,480	$ 462,219	1,655,278	1,818,067	1,988,114
Effect on selling and distribution									1,403,178	1,346,417	1,347,847
Effect on general and administrative									277,659	307,793	342,565
Effect on total operating costs and expenses									1,970,471	1,730,501	1,719,883
Effect on operating income									(315,193)	87,566	268,231
Effect on other (income) expense, net									2,877	1,362	(1,215)
As Without Adoption of ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net sales									7,240,121
Cost of sales									5,584,843
Gross profit									1,655,278
Impact of Adoption of ASU 2014-09 | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net sales									515,162
Cost of sales									515,162	(606,900)	(551,500)
Gross profit									$ 0
As Previously Reported
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cost of sales										5,977,348	5,722,710
Gross profit										1,817,677	1,987,516
Effect on selling and distribution										1,346,948	1,348,349
Effect on general and administrative										311,176	346,028
Effect on total operating costs and expenses										1,734,415	1,723,848
Effect on operating income										83,262	263,668
Effect on other (income) expense, net										(2,942)	(5,778)
Restatement Adjustment | Accounting Standards Update 2017-07
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cost of sales										(390)	(598)
Gross profit										390	598
Effect on selling and distribution										(531)	(502)
Effect on general and administrative										(3,383)	(3,463)
Effect on total operating costs and expenses										(3,914)	(3,965)
Effect on operating income										4,304	4,563
Effect on other (income) expense, net										$ 4,304	$ 4,563