Investment Securities (Gains and losses by category) (Details) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Available For Sale Securities Continuous Unrealized Loss Position Amortized Cost [Abstract]
Available for sale - Amortized cost - less than 12 month	$ 335,079,000	$ 180,338,000
Available for sale - Amortized cost - more than 12 month	38,563,000	121,141,000
Total Available for Sale Amortization cost	373,642,000	301,479,000
Available For Sale Securities Continuous Unrealized Loss Position Aggregate Losses [Abstract]
Available for sale - Unrealized Loss - less than 12 month	5,723,000	1,869,000
Available for sale - Unrealized Loss - more than 12 month	1,400,000	6,480,000
Total Available for Sale Unrealized Loss	7,123,000	8,349,000
Available For Sale Securities Continuous Unrealized Loss Position Fair Value [Abstract]
Available for sale - Fair Value - less than 12 month	329,356,000	178,469,000
Available-for-sale, Fair Value - more than 12 month	37,163,000	114,661,000
Total Available for Sale Fair Value	366,519,000	293,130,000
Continuous Unrealized Loss Position Amortized Cost [Abstract]
Held to Maturity - Amortized cost - less than 12 month	525,258,000	493,519,000
Held to Maturity - Amortized Cost	525,258,000	493,519,000
Held To Maturity Securities, Continuous Unrealized Loss Position Aggregate Losses [Abstract]
Held to Maturity- Unrealized Loss - less than 12 month	7,266,000	5,936,000
Held to Maturity- Unrealized Loss	7,266,000	5,936,000
Held To Maturity Securities Continuous Unrealized Loss Position Fair Value [Abstract]
Held-to-Maturity - Fair Value - less than 12 Month	517,992,000	487,583,000
Held to Maturity - Fair Value	517,992,000	487,583,000
Investment Securities Continuous Unrealized Loss Position [Abstract]
Investment Securities - Amortized Cost	898,900,000	794,998,000
Investment Securities - Unrealized Loss	14,389,000	14,285,000
Investment Securities - Fair Value	884,511,000	780,713,000
CMO's issued by us government sponsored agencies at loss
Available For Sale Securities Continuous Unrealized Loss Position Amortized Cost [Abstract]
Available for sale - Amortized cost - less than 12 month	67,777,000	25,736,000
Available for sale - Amortized cost - more than 12 month	33,883,000	103,340,000
Total Available for Sale Amortization cost	101,660,000	129,076,000
Available For Sale Securities Continuous Unrealized Loss Position Aggregate Losses [Abstract]
Available for sale - Unrealized Loss - less than 12 month	1,430,000	331,000
Available for sale - Unrealized Loss - more than 12 month	793,000	2,410,000
Total Available for Sale Unrealized Loss	2,223,000	2,741,000
Available For Sale Securities Continuous Unrealized Loss Position Fair Value [Abstract]
Available for sale - Fair Value - less than 12 month	66,347,000	25,405,000
Available-for-sale, Fair Value - more than 12 month	33,090,000	100,930,000
Total Available for Sale Fair Value	99,437,000	126,335,000
Obligation of Puerto Rico Government and public instrumentalities at loss
Available For Sale Securities Continuous Unrealized Loss Position Amortized Cost [Abstract]
Available for sale - Amortized cost - more than 12 month	4,680,000	17,801,000
Total Available for Sale Amortization cost	4,680,000	17,801,000
Available For Sale Securities Continuous Unrealized Loss Position Aggregate Losses [Abstract]
Available for sale - Unrealized Loss - more than 12 month	607,000	4,070,000
Total Available for Sale Unrealized Loss	607,000	4,070,000
Available For Sale Securities Continuous Unrealized Loss Position Fair Value [Abstract]
Available-for-sale, Fair Value - more than 12 month	4,073,000	13,731,000
Total Available for Sale Fair Value	4,073,000	13,731,000
FNMA and FHLMC [Member]
Available For Sale Securities Continuous Unrealized Loss Position Amortized Cost [Abstract]
Available for sale - Amortized cost - less than 12 month	184,782,000	149,480,000
Total Available for Sale Amortization cost	184,782,000	149,480,000
Available For Sale Securities Continuous Unrealized Loss Position Aggregate Losses [Abstract]
Available for sale - Unrealized Loss - less than 12 month	3,036,000	1,509,000
Available for sale - Unrealized Loss - more than 12 month		0
Total Available for Sale Unrealized Loss	3,036,000	1,509,000
Available For Sale Securities Continuous Unrealized Loss Position Fair Value [Abstract]
Available for sale - Fair Value - less than 12 month	181,746,000	147,971,000
Total Available for Sale Fair Value	181,746,000	147,971,000
Continuous Unrealized Loss Position Amortized Cost [Abstract]
Held to Maturity - Amortized cost - less than 12 month	525,258,000	468,487,000
Held to Maturity - Amortized Cost	525,258,000	468,487,000
Held To Maturity Securities, Continuous Unrealized Loss Position Aggregate Losses [Abstract]
Held to Maturity- Unrealized Loss - less than 12 month	7,266,000	5,865,000
Held to Maturity- Unrealized Loss	7,266,000	5,865,000
Held To Maturity Securities Continuous Unrealized Loss Position Fair Value [Abstract]
Held-to-Maturity - Fair Value - less than 12 Month	517,992,000	462,622,000
Held to Maturity - Fair Value	517,992,000	462,622,000
Government National Mortgage Association Certificates and Obligations (GNMA) [Member]
Available For Sale Securities Continuous Unrealized Loss Position Amortized Cost [Abstract]
Available for sale - Amortized cost - less than 12 month	29,445,000
Total Available for Sale Amortization cost	29,445,000
Available For Sale Securities Continuous Unrealized Loss Position Aggregate Losses [Abstract]
Available for sale - Unrealized Loss - less than 12 month	620,000
Total Available for Sale Unrealized Loss	620,000
Available For Sale Securities Continuous Unrealized Loss Position Fair Value [Abstract]
Available for sale - Fair Value - less than 12 month	28,825,000	5,093,000
Total Available for Sale Fair Value	28,825,000	5,093,000
Obligation of US Government sponsored agencies at loss [Member]
Available For Sale Securities Continuous Unrealized Loss Position Amortized Cost [Abstract]
Available for sale - Amortized cost - less than 12 month	3,903,000	5,122,000
Total Available for Sale Amortization cost	3,903,000	5,122,000
Available For Sale Securities Continuous Unrealized Loss Position Aggregate Losses [Abstract]
Available for sale - Unrealized Loss - less than 12 month	19,000	29,000
Total Available for Sale Unrealized Loss	19,000	29,000
Available For Sale Securities Continuous Unrealized Loss Position Fair Value [Abstract]
Available for sale - Fair Value - less than 12 month	3,884,000
Total Available for Sale Fair Value	3,884,000
US Treasury Securities at loss
Available For Sale Securities Continuous Unrealized Loss Position Amortized Cost [Abstract]
Available for sale - Amortized cost - less than 12 month	49,172,000
Total Available for Sale Amortization cost	49,172,000
Available For Sale Securities Continuous Unrealized Loss Position Aggregate Losses [Abstract]
Available for sale - Unrealized Loss - less than 12 month	618,000
Total Available for Sale Unrealized Loss	618,000
Available For Sale Securities Continuous Unrealized Loss Position Fair Value [Abstract]
Available for sale - Fair Value - less than 12 month	48,554,000
Total Available for Sale Fair Value	$ 48,554,000
Continuous Unrealized Loss Position Amortized Cost [Abstract]
Held to Maturity - Amortized cost - less than 12 month		25,032,000
Held to Maturity - Amortized Cost		25,032,000
Held To Maturity Securities, Continuous Unrealized Loss Position Aggregate Losses [Abstract]
Held to Maturity- Unrealized Loss - less than 12 month		71,000
Held to Maturity- Unrealized Loss		71,000
Held To Maturity Securities Continuous Unrealized Loss Position Fair Value [Abstract]
Held-to-Maturity - Fair Value - less than 12 Month		24,961,000
Held to Maturity - Fair Value		$ 24,961,000

Amortized cost of investments in available-for-sale securities that have been in a loss position.

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Amortized cost of investments in available-for-sale securities that have been in a loss position for less than twelve months.

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Amortized cost of investments in available-for-sale securities that have been in a loss position for more than twelve months.

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Amortized cost of investments in held-to-maturity securities that have been in a loss position for less than twelve months.

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Aggregate losses of investments in securities that have been in a loss position.

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Amortized cost of investments in securities that have been in a loss position.

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Fair Value of investments in securities that have been in a loss position.

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Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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Amount of unrealized loss on securities classified as available-for-sale.

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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Amount of unrealized loss before deducting unrealized gain on investments in held-to-maturity securities that have been in a loss position for less than twelve months.

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