GBG Acquisition - Allocation and Proforma (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2019	Dec. 31, 2018
Intangible assets and liabilities acquired:
Goodwill			$ 356,814	$ 376,132
Pro forma financial information (unaudited)
Net sales	$ 605,710	$ 1,586,177
Cost of goods sold	495,826	1,250,806
Gross margin	$ 109,884	$ 335,371
Gross margin % of net sales	18.10%	21.10%
Operating expenses
Selling, general and administrative	$ 151,607	$ 431,491
Depreciation and amortization	22,177	68,526
Total operating expenses	173,784	500,017
Operating loss	(63,900)	(164,646)
Interest expense	38,066	114,131
Other (income) expense, net	22	(17,551)
Loss before income taxes	(101,988)	(261,226)
Income tax benefit	(1,152)	(2,275)
Net loss	$ (100,836)	$ (258,951)
GBG
Assets acquired and liabilities assumed:
Accounts receivable			65,434
Inventories			393,303
Prepaid expenses and other current assets			56,380
Property and equipment			86,971
Other assets			41
Accounts payable and accrued expenses			(592,557)
Intangible assets and liabilities acquired:
Goodwill			348,407
Leasehold interests			(2,310)
Customer relationships			824,000
Preliminary purchase price			1,179,669
GBG | Preliminary Purchase Price Allocation
Assets acquired and liabilities assumed:
Accounts receivable			65,106
Inventories			371,605
Prepaid expenses and other current assets			56,380
Property and equipment			86,971
Other assets			41
Accounts payable and accrued expenses			(589,849)
Intangible assets and liabilities acquired:
Goodwill			367,725
Leasehold interests			(2,310)
Customer relationships			824,000
Preliminary purchase price			1,179,669
GBG | Measurement Period Adjustments
Assets acquired and liabilities assumed:
Accounts receivable			328
Inventories			21,698
Accounts payable and accrued expenses			(2,708)
Intangible assets and liabilities acquired:
Goodwill			$ (19,318)