Shareholders' Equity (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Nov. 13, 2014
Dividends per share (in dollars per share)	$ 0.76	$ 0.76	$ 0.76
Treasury stock, shares acquired (in shares)		0
Treasury Stock, Value, Acquired, Cost Method	$ 15,000,000.0
Remaining authorized repurchase amount	$ 145,700,000
Share repurchase program 2015
Authorized repurchase amount				$ 500,000,000.0
Treasury stock, shares acquired (in shares)	324,889	0	0

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
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