Stockholders' Equity (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Changes in other comprehensive income (loss)
Balance at the beginning of the period	$ (46,797)
Other comprehensive income before reclassification	42,124
Amount reclassified from accumulated other comprehensive income	(11,186)
Net current period other comprehensive income	30,938
Balance at the end of the period	(15,859)
Unrealized gains on investment securities
Changes in other comprehensive income (loss)
Balance at the beginning of the period	1,823
Other comprehensive income before reclassification	10,447
Amount reclassified from accumulated other comprehensive income	(9,120)
Net current period other comprehensive income	1,327
Balance at the end of the period	3,150
Change in valuation allowance for unrealized gains (losses) on investment securities
Changes in other comprehensive income (loss)
Balance at the beginning of the period	32
Other comprehensive income before reclassification	6,085
Amount reclassified from accumulated other comprehensive income	(5,307)
Net current period other comprehensive income	778
Balance at the end of the period	810
Pension and postretirement benefits
Changes in other comprehensive income (loss)
Balance at the beginning of the period	(48,652)
Other comprehensive income before reclassification	25,592
Amount reclassified from accumulated other comprehensive income	3,241
Net current period other comprehensive income	28,833
Balance at the end of the period	$ (19,819)