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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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

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The expenses and losses recorded for each transaction with the acquiree that was recognized separately from the acquisition of assets and assumptions of liabilities in the business combination.

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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.

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Acquisitions (Narrative) (Details) (USD $)	0 Months Ended	3 Months Ended
Acquisitions (Narrative) (Details) (USD $)	Sep. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$ 235,523,000us-gaap_Goodwill		$ 236,044,000us-gaap_Goodwill
September 2013 Acquisition
Business Acquisition [Line Items]
Total acquisition related costs		(228,000)	208,000
Aggregate purchase consideration			7,454,000
Fair value of business acquisition obligation	2,322,000	305,000
Goodwill		2,466,000	2,466,000
Selling, general and administrative costs \| September 2013 Acquisition
Business Acquisition [Line Items]
Total acquisition related costs		(228,000)	2,000
Adjustment to payable, expense recorded		228,000
Interest Expense \| September 2013 Acquisition
Business Acquisition [Line Items]
Adjustment to payable, expense recorded		$ (4,000)