Subsequent events	12 Months Ended
Dec. 31, 2019
Subsequent events
Subsequent events	26. SUBSEQUENT EVENTS Deal Contingent Hedge On February 11, 2020, in connection with the MDA Agreement, the Company entered into deal-contingent foreign currency hedge arrangements, with no cash cost, to hedge 50% of the Canadian dollar denominated sales price at a spot rate of $1.338362 to C$1.00, if the closing date occurs on or before June 29, 2020. Fees associated with these arrangements are contingent and payable upon closing of the acquisition and will vary based on the closing date.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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