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New accounting standards Debt Issuance Costs (Details) - Accounting Standards Update 2015-03 [Member] - Restatement adjustment [Member] - USD ($)	Dec. 31, 2015	Mar. 31, 2015
Prepayments and other current assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclass of debt issuance costs, current	$ 100,000	$ 100,000
Other [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclass of debt issuance costs, non-current	$ 6,000,000	$ 5,500,000

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