Number Of Acquisitions Completed

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- Definition

Number of Branch Locations

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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- Definition

The number of businesses acquired by the entity during the period.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Acquisitions - Narrative (Details) $ in Thousands	3 Months Ended								12 Months Ended
Acquisitions - Narrative (Details) $ in Thousands	Dec. 31, 2018 USD ($) branch	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) acquisition branch	Dec. 31, 2017 USD ($) acquisition	Oct. 01, 2018 location	Aug. 01, 2018 location	Feb. 01, 2018 location	Nov. 01, 2017 location	Oct. 01, 2017 location	Aug. 01, 2017 location	Jul. 01, 2017 location	May 01, 2017 location	Apr. 03, 2017 location	Jan. 03, 2017 location
Business Acquisition [Line Items]
Number of branch locations \| branch	175								175
Net sales \| $	$ 516,159	$ 542,273	$ 522,219	$ 463,661	$ 443,674	$ 467,891	$ 460,086	$ 418,463	$ 2,044,312	$ 1,790,114
Income from operations \| $									$ (12,183)	82,480
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Number of businesses acquired \| acquisition									4
Consideration transferred \| $									$ 94,100	$ 74,600
Number of acquisitions completed \| acquisition										9
2018 Acquisitions
Business Acquisition [Line Items]
Net sales \| $									62,900
Income from operations \| $									2,600
2017 Acquisitions
Business Acquisition [Line Items]
Net sales \| $										$ 68,800
Income from operations \| $										3,800
Minimum \| Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Consideration transferred \| $									6,200	700
Maximum \| Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Consideration transferred \| $									49,300	20,600
South Dakota and Iowa \| Agan
Business Acquisition [Line Items]
Number of branch locations											3
Pennsylvania and Virginia \| Ciesco
Business Acquisition [Line Items]
Number of branch locations												6
Minnesota, North Dakota, South Dakota and Nebraska \| ArmCom
Business Acquisition [Line Items]
Number of branch locations													5
Missouri \| RM Supply
Business Acquisition [Line Items]
Number of branch locations													2
Virginia and North Carolina \| Dominion Interior Supply
Business Acquisition [Line Items]
Number of branch locations																				4
Pennsylvania \| Irwin
Business Acquisition [Line Items]
Number of branch locations																			1
Minneapolis-St. Paul Metropolitan Area \| Wallboard, Inc.
Business Acquisition [Line Items]
Number of branch locations																		2
Washington \| Gypsum Wallboard Supply, Inc
Business Acquisition [Line Items]
Number of branch locations																		1
Missouri, Illinois and Kentucky \| Ceiling & Wall Supply
Business Acquisition [Line Items]
Number of branch locations																	5
Virginia \| Virginia Builders' Supply, Inc
Business Acquisition [Line Items]
Number of branch locations																	1
Tennessee and Mississippi \| American Wal-Board
Business Acquisition [Line Items]
Number of branch locations																2
Texas \| MCS Door & Hardware
Business Acquisition [Line Items]
Number of branch locations															1
Canada
Business Acquisition [Line Items]
Net sales \| $									$ 223,723	$ 214,614
Canada \| Del-Pro Building Supplies, Inc
Business Acquisition [Line Items]
Number of branch locations														1