Accumulated Other Comprehensive Loss (Textual) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013
Accumulated Other Comprehensive Loss (Textual) [Abstract]
Net unrealized gains (losses) on investment securities-available-for-sale, tax expense (benefit)	$ (478)	$ (1,335)	$ 2,232
Pension and other postretirement benefits adjustment, tax benefit	$ 9,915	$ 9,714	$ 18,726

Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax Expense

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant