Subsequent events	12 Months Ended
Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent events	Subsequent events On January 29, 2020, our Board of Directors declared a quarterly cash dividend of $0.26 per common share, payable on March 9, 2020, to stockholders of record on February 18, 2020. On January 15, 2020, we closed on the sale of our wholly-owned subsidiary AWR Corporation to Cadence Design Systems Inc. for a total of approximately $160 million in cash. We expect to recognize a gain on the divestment of approximately $123 million, net of taxes, during the first quarter of 2020.

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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