Capital Stock - Common Stock (Details) - USD ($) $ / shares in Units, shares in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Feb. 28, 2022
Class of Stock [Line Items]
Stock repurchase program, increase in authorized amount	$ 73,000,000
Stock repurchase program, authorized amount	250,000,000	$ 250,000,000		$ 250,000,000
Stock repurchased during period (in shares)		5.8	5.4	5.8	5.4
Stock repurchased during period, average price (in dollars per share)		$ 5.66	$ 9.10	$ 5.66	$ 9.10
Stock repurchased during period		$ 33,102,000	$ 48,886,000	$ 33,102,000	$ 48,886,000
Remaining authorized repurchase amount	$ 217,000,000	217,000,000		217,000,000
Common dividends declared		42,077,000	$ 77,806,000	96,250,000	$ 156,408,000
Securities excluded from computation of EPS (in shares)			2.3		2.3
Regular Dividend
Class of Stock [Line Items]
Common dividends declared		$ 42,000,000	$ 78,000,000	$ 96,000,000	$ 156,000,000
Dividends declared per share of common stock (in dollars per share)		$ 0.18	$ 0.33	$ 0.41	$ 0.66
Sales Agreements
Class of Stock [Line Items]
Aggregate offering price						$ 500,000,000