For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the best estimate at the acquisition date of the contractual cash flows not expected to be collected, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of the receivables acquired, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

+ Details

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

+ Details

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- Details

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- Details

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- Definition

Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

+ References

+ Details

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- Details

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 55

-Paragraph 37

-URI http://asc.fasb.org/extlink&oid=25498275&loc=d3e2207-128464

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- Definition

The amount of inventory recognized as of the acquisition date.

+ References

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Period Type:	instant

- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

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Period Type:	instant

- Definition

Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Balance Type:	credit
Period Type:	instant

- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

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Balance Type:	debit
Period Type:	instant

- Definition

Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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- Details

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(Assets Acquired and Liabilities Assumed - Pipe and Foundation Group) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	May 01, 2013
Fair value of consideration transferred:
Cash	$ 611,087	$ 178,309	$ 0
Intangible assets:
Goodwill	62,016us-gaap_Goodwill	62,016us-gaap_Goodwill	29,990us-gaap_Goodwill
Pipe and Foundation Group [Member]
Fair value of consideration transferred:
Cash				178,309
Preliminary allocation of consideration transferred to net assets acquired:
Accounts receivable				17,695
Inventories				25,948
Property, plant and equipment				31,261
Intangible assets:
Current liabilities				(10,595)
Other liabilities				(26)
Total identifiable net assets				146,283
Goodwill				32,026
Consideration transferred				178,309
Fair value of accounts receivable acquired				17,695
Gross contractual amount of acquired receivables				17,772
Amount of acquired receivables expected to be uncollectible				77
Pipe and Foundation Group [Member] \| Trademarks [Member]
Intangible assets:
Intangible assets				5,200
Pipe and Foundation Group [Member] \| Customer relationships [Member]
Intangible assets:
Intangible assets				57,600
Pipe and Foundation Group [Member] \| Developed Technology Rights [Member]
Intangible assets:
Intangible assets				18,900
Pipe and Foundation Group [Member] \| Other [Member]
Intangible assets:
Intangible assets				$ 300