Share-Based Compensation Plans Restricted share unit activity (Details) (Restricted share units (RSUs) [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Restricted share units (RSUs) [Member]
Non-vested share awards (in shares)
Non-vested at beginning of period	9,759		10,432
Granted	1,146		1,764
Vested	(1,950)		(2,080)
Forfeited	(125)		(128)
Non-vested at end of period	8,830		9,988
Weighted Average Fair value (in dollars per share)
Non-vested at beginning of period	$ 51	[1]	$ 44	[1]
Granted	$ 83	[1]	$ 60	[1]
Vested	$ 51	[1]	$ 46	[1]
Forfeited	$ 50	[1]	$ 44	[1]
Non-vested at end of period	$ 56	[1]	$ 47	[1]

[1] Represents per share weighted average fair value of award at date of grant