Capital Stock - Additional Information (Detail) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | |
|---|---|---|---|
Mar. 31, 2017 |
Jun. 30, 2017 |
Jun. 30, 2016 |
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| Schedule of Capitalization, Equity [Line Items] | |||
| Common shares repurchased | 1,400,000 | ||
| Common shares repurchased, value | $ 550 | $ 575 | |
| Shares authorized to be repurchased | 7,600,000 | ||
| Series C Non-voting Participating Preferred Stock [Member] | PNC [Member] | |||
| Schedule of Capitalization, Equity [Line Items] | |||
| Surrender of share of series non- voting preferred stock | 517,138 | ||
| X | ||||||||||
- Definition Surrender of share of series non- voting preferred stock. No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan. No definition available.
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- Definition Number of shares that have been repurchased during the period and are being held in treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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