Accumulated Other Comprehensive Loss (Textual) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Accumulated Other Comprehensive Loss (Textual) [Abstract]
Net unrealized gains (losses) on investment securities-available-for-sale, tax expense (benefit)	$ 946	$ (113)	$ (478)
Pension and other postretirement benefits adjustment, tax benefit	$ 16,981	$ 17,362	$ 9,915

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

No definition available.

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Balance Type:	credit
Period Type:	instant